ATI Infection Medications Antibiotics Nursing Notes PDF

Antibacterial: Medications That Inhibit DNA Replication/Cell Division - Fluoroquinolones One type of bactericidal antibiotic that treats infections also inhibits DNA replication and cell division. These are the fluoroquinolones. Fluoroquinolones treat a wide range of bacterial infections, including...

Antibacterial: Medications That Inhibit DNA Replication/Cell Division - Fluoroquinolones One type of bactericidal antibiotic that treats infections also inhibits DNA replication and cell division. These are the fluoroquinolones. Fluoroquinolones treat a wide range of bacterial infections, including severe urinary tract infections. They also protect clients from anthrax after exposure to or inhalation of its spores. Oral fluoroquinolones are extremely valuable in that they can treat clients with serious infections in a home setting. Prototype and Other Medications Medication Classification-Fluoroquinolones(anti-infective) The prototype medication for fluoroquinolones is ciprofloxacin. Other medications in this category are ofloxacin, levofloxacin, and moxifloxacin. Expected Pharmacologic Action Fluoroquinolones cause the death of susceptible bacterial cells by inhibiting the two enzymes necessary for the replication of DNA and cell division, DNA gyrase and topoisomerase IV. They are also bactericidal against many aerobic gram-negative bacteria, some aerobic gram-positive bacteria, and very few anaerobic bacteria. Adverse Drug Reactions Fluoroquinolones can cause mild CNS manifestations, such as dizziness and headache, as well as confusion in older adults. Its gastrointestinal side effects include nausea, vomiting, abdominal pain, and diarrhea. An unusual adverse effect of these medications is rupture of the Achilles tendon. Although this is rare, it occurs primarily in older clients, clients taking glucocorticoids, and those with a history of heart, lung, or kidney transplants. Because of this possibility, systemic ciprofloxacin is avoided in children under the age of 18. You will also learn that these medications are similar to tetracyclines in that they cause photosensitivity. This happens when a client's skin reacts to ultraviolet light after direct or indirect exposure to the sun or a sunlamp, and the reaction manifests as a sunburn. This reaction may be quite severe and occur despite the use of sunscreen. Severe adverse reactions can include seizures, increased intracranial pressure, suicidal ideation, hepatotoxicity, anaphylaxis, and Clostridium difficile-associated diarrhea (CDAD). Interventions When caring for clients taking fluoroquinolones, monitor them for CNS manifestations, especially confusion in older adults, as well as assess clients for suicidal ideation. Also, monitor them for gastrointestinal manifestations, including Clostridium difficile-associated diarrhea (DAD), which may signify that a decrease in the dose needs to occur. Another important effect of this medication to monitor for and report is Achilles tendon pain. This typically occurs in high-risk populations, as noted above. If this occurs, be sure that discontinuation of the medication occurs, which will prevent the tendon from rupturing. Lastly, do not allow clients to go outdoors without first covering their skin fully with clothing and applying sunscreen to areas of exposure. This will help prevent photosensitivity. As with any other anti-infective, monitor the client for anaphylaxis manifestations. Administration Ciprofloxacin is available in oral and IV forms. When giving the oral form, administer antacids, iron and calcium supplements, and sucralfate 2 hr after or 6 hr before ciprofloxacin. When giving ciprofloxacin by IV, infuse it slowly for at least 60 min. Also, be sure to follow the manufacturer's recommendations for dilution. IV ciprofloxacin is incompatible with many other medications. So, remember, do not mix it with another medication. Give it through a separate lumen in a multi- lumen IV catheter or designate an IV line just for it. Client Instructions Instruct clients taking a fluoroquinolone to report CNS manifestations to their provider. Also, recommend that they decrease their caffeine intake with this medication, because caffeine can cause an increase in CNS manifestations as well as facilitate dehydration. Encourage clients to consume at least 1,500 to 2,000 mL of fluids/day. Gastrointestinal manifestations may be another important side effect they need to report. Tell clients to report tendon pain due to the risk of Achilles tendon rupture. Tell clients to take antacids, iron and calcium supplements, dairy products, and sucralfate 2 hr after or 6 hr before taking oral ciprofloxacin. Caution client on driving or operating machinery if they experience dizziness or drowsiness. Safety Alert The photoactivation of chemicals in fluoroquinolones by sunlight can cause a phototoxic reaction, which manifests as a severe sunburn. Itching, rash, and hives can accompany the sunburn. Make sure clients understand the importance of completely avoiding sunlight or wearing clothing that fully covers their body. Tell them to apply sunscreen of at least 30 SPF to areas of exposure. Sunscreens, which also contain zinc oxide, provide extra protection from the sun. If a photosensitive reaction does occur, treat it with cold compresses and topical corticosteroids. Clients need to avoid sunlamp exposure altogether when taking this Medication. Contraindications and Precautions If clients are allergic to any fluoroquinolones, they should not take ciprofloxacin. Those with tendon pain also need to avoid it. Use caution when giving fluoroquinolones to clients who have a serious CNS disorder, such as seizures, gastrointestinal disorders, depression, or renal impairment. Also, take precautions when giving these medications to clients receiving warfarin. In general, only give fluoroquinolones to children who are under 18 or to pregnant clients when the benefits outweigh the risks, providing there are no allergies to the medication. Clients with myasthenia gravis may experience worsening manifestations. Antiarrhythmic medications can prolong the QT interval. Interactions Antacids, iron preparations, calcium, including dairy products, and sucralfate decrease the absorption of fluoroquinolones. Concurrent use of erythromycin, quinidine, some antipsychotics, and tricyclic antidepressants can increase the risk for torsade de pointes in those susceptible. Increased hypoglycemia may occur when taken concurrently with antidiabetic medication. Antibacterial: Antibiotics That Inhibit Protein Synthesis Aminoglycosides Aminoglycosides are narrow-spectrum antibiotics that treat infections caused by aerobic gram- negative bacilli cause. They commonly treat Escherichia coli, Klebsiella pneumoniae,and Pseudomonas aeruginosa. Gentamicin, in combination with another antibiotic, helps treat severe infections that some gram-positive cocci cause. It is also available in topical form to treat skin and eye infections.x Prototype and Other Medications Medication Classification-Aminoglycosides(anti-infectives) The prototype medication for aminoglycosides is gentamicin. Other medications in this category are amikacin, tobramycin, and neomycin. Expected Pharmacologic Action Aminoglycosides are the third type of antibiotic that inhibits protein synthesis. They also inhibit transfer RNA from binding with messenger RNA. This synthesizes abnormal proteins due to incorrect reading of the genetic code. Then, a leaky cell wall will eventually cause death. Aminoglycosides are also bactericidal. So, larger doses destroy bacteria faster, and they are most effective against gram-negative aerobic bacilli. Adverse Drug Reactions The main adverse effect of aminoglycosides ototoxicity. This happens when trough levels of the medication elevate above the acceptable reference range. Early signs of ototoxicity include tinnitus, headache, ataxia, and vertigo. Nephrotoxicity is another potential adverse effect, manifested by polyuria, dilute urine, protein and casts in the urine, and an elevation in BUN and Creatinine. Interventions When caring for a client taking an aminoglycoside, monitor for reports of tinnitus, headache, and vertigo, which you need to report to the provider. Evaluation by audiometry of the eighth cranial nerve function should be conducted prior to and throughout treatment. To minimize the risk for ototoxicity, monitor the trough blood levels frequently for the aminoglycoside medication being given. Intake and output should be monitored for hydration status as well as kidney function. To reduce the risk of nephrotoxicity, regularly monitor the laboratory values that reflect kidney function. These include BUN, creatinine, and checking the urine for protein and casts. Call the provider if elevations in any of these values occur. Aminoglycosides should be limited to no more than 10 days of treatment to prevent these serious adverse effects. Safety Alert The nephrotoxic effects of aminoglycosides increase if blood levels are above the therapeutic level. If a client's kidneys cannot excrete the medication as fast as it is being ingested, nephrotoxicity can occur. To determine if the medication's peak level is within therapeutic levels, measure the medication's blood concentration 30 min after an IM injection and 30 min after the completion of an IV infusion. Trough levels are drawn approximately one hour prior to the next dose of medication. To evaluate clients' kidney function, get baseline values for creatinine clearance as well as BUN and creatinine. Continue to monitor them on a regular basis during therapy. If the peak or trough blood level is above the target reference range set for the client or the kidney function tests show an increase in values, notify the provider. Administration Aminoglycosides are available in topical, ophthalmic, IM, IV, and intrathecal forms. When giving ophthalmic drops, gently press at the inner canthus for 1 to 2 min after instilling drops. This will help prevent systemic absorption through the puncta and lacrimal sac. Also, clients need to shut their eyes for 1 to 2 min to maximize local absorption. When applying a topical cream containing an aminoglycoside, do not apply it to large skin areas. This will reduce the risk of toxicity and systemic absorption. Neomycin, the active ingredient in topical aminoglycosides, is extremely ototoxic and nephrotoxic. So, use it sparingly. For IM injections, inject the aminoglycoside deep into a large muscle. For IV forms of the medication, give it as an intermittent infusion, using the manufacturer's recommendations for rate and dilution. Lastly, when giving it intrathecally, use a preservative-free form, and throw away portions you do not use. Client Instructions Reinforce with clients the importance of immediately calling the provider at the onset of tinnitus, headache, vertigo, or hearing loss when taking an aminoglycoside. Clients should be encouraged to drink plenty of fluids; however, they also need to report an increase in output of dilute urine. Contraindications and Precautions Clients who have had an allergic reaction to an aminoglycoside in the past should not receive one again. Use caution when giving aminoglycosides to clients who already have hearing loss due to damage to the acoustic nerve. Also, do not give this medication to clients who have a form of tinnitus or vertigo or have renal or chronic neuromuscular disorders. Those experiencing dehydration should be hydrated before beginning therapy. Use with caution in clients with neuromuscular disorders such as myasthenia gravis. Tobramycin and streptomycin may cause congenital deafness, so they should not be administered to pregnant clients. Interactions Avoid concurrent use with other ototoxic or nephrotoxic medications (aspirin, macrolides, loop diuretics, NSAIDs) as it can increase the risks to clients. Cephalosporins, vancomycin, and penicillin enhance the bactericidal effect of gentamicin. Do not mix gentamicin in the same IV solution with other medications such as penicillin, cephalosporins, and heparin. Finally, aminoglycosides, in combination with neuromuscular blockers, such as pancuronium or succinylcholine, can prolong respiratory paralysis. Antibacterial: Antibiotics That Inhibit Protein Synthesis Macrolides Macrolides are broad-spectrum antibiotics that inhibit protein synthesis. They are a first-line treatment for Legionnaires' disease, whooping cough, and acute diphtheria. Also, clients who are carriers of diphtheria, have chlamydia infections, or certain types of pneumonia take macrolides. These medications can also treat common infections in clients with an allergy to penicillin. And there is an ophthalmic form that you can use to prevent eye infections in neonates. Prototype and Other Medications Medication Classification - Macrolides (anti-infectives) The prototype medication for macrolides is erythromycin. Other medications in this category are azithromycin and clarithromycin. Expected Pharmacologic Action Macrolides inhibit protein synthesis. They do this by inhibiting the transfer RNA from binding with messenger RNA. Then, amino acids cannot be added to the peptide chain. This then blocks bacterial protein synthesis, and bacteria cannot replicate. Macrolides are bacteriostatic antibiotics because they block the reproduction of bacteria. If you give them in large doses or to organisms that are extremely sensitive to the medication, they may become bactericidal. Macrolides are also bacteriostatic against gram-positive bacteria and some gram-negative bacteria. Adverse Drug Reactions Common adverse effects of macrolides include gastrointestinal symptoms, such as nausea, vomiting, abdominal pain, and diarrhea. Rarely, they can also cause ventricular dysrhythmias, resulting in death. This happens when there is a prolonging in the QT interval on the electrocardiogram (ECG) and can cause sudden death from ventricular dysrhythmias. Avoiding certain antidysrhythmic medications when taking a macrolide will decrease this risk. And, like vancomycin, ototoxicity is a potential adverse effect of macrolides, which can cause transient hearing loss, vertigo, and tinnitus. Finally, like other broad-spectrum antibiotics, there is a risk for superinfections, such as Clostridium difficile-associated diarrhea (CAD) or candidiasis. Interventions When caring for clients receiving a macrolide antibiotic, monitor them for nausea, vomiting, abdominal pain, and diarrhea. Report these findings to see if the provider wants to decrease the dose to minimize the manifestations. Blood work should be monitored for liver function when there is long-term use. By evaluating all medications that the client is taking, you can see which ones may interact with the prescribed erythromycin. Then you can ask the provider if the macrolide dose should be reduced or stop one of the other medications. It is also important to monitor for and report manifestations of ototoxicity. If you note any, tell the provider so they can lower the dosage. Before giving a macrolide, ask clients whether they have been informed of any cardiac abnormalities, specifically a prolonged QT interval. And always monitor for and report manifestation of a superinfection. Safety Alert Concurrent administration of erythromycin with medications that are CPY3A inhibitors can significantly decrease erythromycin's metabolism, as well as cause a concurrent increase its blood level. CPY3A inhibitors are enzymes that assist with the metabolism and breakdown of several types of medications, erythromycin being one of them. Other medications that are CPY3A inhibitors include azole antifungals, protease inhibitors, which help treat HIV, and diltiazem and verapamil, both of which are calcium-channel blockers and treat hypertension and cardiac dysrhythmias. Because increased blood levels of erythromycin can cause an increase in QT intervals, life-threatening ventricular tachycardia can result, which is known as torsades de pointes. Administration Erythromycin is available in four different forms. First is erythromycin base, which is available as tablets, capsules, and topical ophthalmic ointment. Erythromycin stearate is available as tablets. Erythromycin ethyl succinate, also called EES, is also available as tablets. Finally, erythromycin lactobionate is available in IV form. Clients need to take erythromycin base and erythromycin stearate on an empty stomach 1 hr before or 2 hr after a meal, which will help with absorption. Then they need to drink 8 oz of water. If they experience gastrointestinal manifestations, they can take the medication with food. Clients can also take erythromycin with an enteric coating with or without meals. That is because the medication does not dissolve until it reaches the small intestine. When giving the IV form, follow the recommendations for dilution and rate. This helps prevent thrombophlebitis at the IV site. Client Instructions If gastrointestinal manifestations occur, instruct clients to take a macrolide antibiotic with food. If this does not relieve the manifestations, notify the provider. You need to emphasize how important it is that clients report heart palpitations or fainting spells to their provider. They also need to call about hearing loss, vertigo, tinnitus, or bloody or watery diarrhea. Clients can also experience mouth pain with white patches on their oral mucosa. Vaginal discomfort with discharge can occur. The client needs to contact the provider about both. Contraindications and Precautions It is important that clients who are allergic to erythromycin or another macrolide antibiotic not take erythromycin. This also applies to clients with a history of long QT syndrome. Take precautions when giving erythromycin to clients with gastrointestinal or liver disorders, as well as hypokalemia and hypomagnesemia. Interactions Erythromycin decreases the blood levels of chloramphenicol and clindamycin antibiotics. However, it increases the blood levels of multiple medications, including digoxin, warfarin, and theophylline. Medications that inhibit the CYP3A4 enzyme, such as verapamil, azole antifungals, protease inhibitors for HIV, and diltiazem, will increase erythromycin levels and could cause hypotension. Pimozide increases the risk of serious arrhythmias. Medication Therapy for Bacterial Infections Antibacterial: Antibiotics That Inhibit Protein Synthesis Tetracyclines There are multiple types of antibiotics that inhibit bacterial protein synthesis. There are tetracyclines, macrolides, and other bacteriostatic medications such as clindamycin and tigecycline. Then there are the aminoglycosides, such as gentamicin and tobramycin, which are bactericidal. Another category is oxazolidinones. Due to the overuse of tetracyclines, many bacteria are now resistant to them. However, with use declining, they are still the antibiotic of choice for chlamydia and mycoplasma infections. Tetracyclines also treat rickettsia infections, such as typhus and Rocky Mountain spotted fever. Clients with syphilis and gram-negative infections with an allergy to penicillin can receive tetracyclines, too. Lastly, tetracycline is a first-choice treatment for the more uncommon gram-positive infections, such as cholera and anthrax. It can also treat acne vulgaris in both topical and oral forms. Adolescents and adults usually take tetracycline when their acne treatment requires an antibiotic. Prototype and Other Medications Medication Classification-Tetracyclines(anti-infectives) The prototype medication for the tetracyclines is tetracycline. Other antibiotic medications in this include doxycycline and minocycline. Expected Pharmacologic Action Tetracyclines inhibit protein synthesis because they inhibit the transfer of RNA from binding with messenger RNA. Because of this, amino acids cannot be added to the peptide chain. This blocks bacterial protein synthesis, which prohibits the bacteria from replicating. Tetracyclines are also effective against gram-positive and gram-negative bacteria. But this is only if they do not develop resistance. Atypical organisms that tetracyclines are effective against include parasites. For example, tetracyclines prevent malaria in areas where a parasite that causes this disease is Quinine-resistant. Adverse Drug Reactions It is important for you to understand the adverse effects of tetracyclines, which include gastrointestinal manifestations such as nausea, vomiting, diarrhea, and abdominal pain. Tetracyclines have a significant impact on bones (suppression of long-bone growth in premature infants) and teeth (brown or yellow discoloration) and should be avoided by children aged 8 and under. Hepatotoxicity is another adverse effect of this medication, especially when you give it in large doses or to pregnant and postpartum clients. You already know that, like other broad- spectrum antibiotics, superinfections, such as Clostridium difficile-associated diarrhea (CDAD) and Candida albicans, can develop when you take this medication. Finally, tetracyclines significantly increase clients' photosensitivity. This makes them susceptible to a severe sunburn- type reaction with even a moderate amount of sun exposure. Safety Alert Tetracyclines discolor the developing teeth of a fetus, as well as teeth in infants over 4 months and children under 8 years. So, infants, children, and clients who are pregnant should not take this medication. Discoloration occurs when the teeth are developing under the gum line. This embeds in the enamel of the teeth, making an intrinsic stain. Deciduous teeth erupt with a yellow-brown stain, sometimes in a stripe pattern. Use during pregnancy will not affect the coloration of permanent teeth. Permanent teeth are affected when taken by children under the age of 8. Commercial whiteners have no effect on these stains. If clients are self-conscious, veneers or crowns are the most appropriate solution. Interventions Monitor for gastrointestinal disturbance; if gastrointestinal discomfort occurs, clients need to take tetracyclines with non-dairy foods, although food does decrease absorption. It is important to monitor and report the degree of gastrointestinal manifestations. This may indicate that a decrease in the dose is necessary. When preparing to give this medication to clients of childbearing age, ask them if they are pregnant. During tetracycline therapy, monitor liver function tests closely. Observe for manifestations of liver damage, such as jaundice. Also, continually monitor for the manifestation of superinfections. If one, such as Clostridium difficile- associated diarrhea (CDAD), develops, stop the medication. If clients have been in the sun, observe their skin for a sunburn-like reaction. Likewise, monitor bowel function as well as lymphadenopathy and facial swelling. Administration Tetracyclines work best on an empty stomach, so administer this medication 1 hr before or 2 hr after meals. Do not administer this medication right before bedtime. If unable to administer tetracyclines while the client has an empty stomach, make sure it is given with non-dairy food because tetracycline interacts with calcium-containing foods. You will learn more about this interaction in a bit. Give doxycycline with foods that contain calcium. It is also safer to administer to clients with renal failure. The topical form of tetracycline usually treats acne vulgaris, and the intramuscular and intravenous forms are only if the client cannot tolerate the oral form. When giving the liquid form of tetracycline, shake the solution well before measuring the dose in a medication cup. And always ensure that the medication you are giving is not out-of-date because that could precipitate kidney dysfunction. Client Instructions There are several important things you need to tell clients about taking a tetracycline antibiotic. First, to avoid gastrointestinal upset, make sure they know not to take the medication with calcium-containing foods and antacids. If gastrointestinal manifestations become severe, clients need to notify their provider. Otherwise, for better absorption, tell them to try taking the medication on an empty stomach, 1 hr before or 2 hr after meals. If a client becomes pregnant while taking tetracyclines, they need to report this immediately to their provider so they can start another antibiotic. Inform clients that infants and children under 8 should not take this medication. If manifestations of liver damage such as jaundice, abdominal pain, and fatigue develop, client need to report to their provider immediately. Discuss the potential for the development of superinfections and the manifestations they need to watch for, such as mouth pain or difficulty chewing and swallowing, which indicates an oral yeast infection; vaginal irritation and a white, curd-like discharge, which indicates a vaginal yeast infection; and watery or bloody stools, which indicates Clostridium difficile associated diarrhea (CAD). Finally, warn clients about the photosensitivity effects of the medication and how wearing protective clothing and sunscreen during sun exposure decreases the reaction of their skin. Tetracyclines themselves are photosensitive, so tell clients to keep them in a container that protects them from light. Contraindications and Precautions Do not give tetracyclines to clients who are pregnant and to infants and children under 8. Clients allergic to tetracyclines and those undergoing exposure to ultraviolet light should also not take tetracyclines. Use this medication with caution in clients with liver or kidney impairment. Interactions Tetracyclines interact with calcium-containing foods, as well as antacids that contain calcium, magnesium, or aluminum. The medication binds with these chemicals, which inactivates it. Antidiarrheals containing kaolin, dairy products, and supplements that contain iron or zinc decrease the absorption of tetracyclines. It is very important to note that tetracyclines decrease the effectiveness of oral contraceptives. Antibacterial: Medications That Inhibit Folic Acid Synthesis - Sulfonamides Two medications inhibit folic acid synthesis: sulfonamides and urinary tract antiseptics. Both primarily treat urinary tract infections. Sulfonamides were the very first medications used for their antibacterial actions. Sulfonamide antibiotics are synthetic, broad-spectrum antimicrobials. For example, sulfamethoxazole is combined with trimethoprim, another antibiotic that interferes with folic acid synthesis, to treat urinary tract infections, pneumocystis pneumonia, Shigella enteritis (shigellosis), also called traveler's diarrhea, the acute phase of chronic bronchitis, and acute otitis media in children. Prototype and Other Medications Medication Classification-Folate antagonist, sulfonamide (anti-infectives, antiprotozoal) The prototype medication for the sulfonamides is a combination of trimethoprim and sulfamethoxazole. Remember, sulfamethoxazole is only available in combination with trimethoprim. However, trimethoprim is available by itself. Another example of a sulfonamide is oral sulfadiazine. Silver sulfadiazine is a topical sulfonamide medication that is used for the prevention and treatment of infections of burn wounds. Expected Pharmacologic Action Remember that sulfonamide inhibits folic acid synthesis, which is a requirement for the synthesis of DNA, RNA, and cellular proteins. They do this by blocking one step in the synthesis process.Sulfonamides are also bacteriostatic antibiotics and are effective against gram-positive cocci,gram-negative bacilli, and some protozoa and fungi. Adverse Drug Reactions Common adverse effects of sulfonamides include the gastrointestinal manifestations of nausea and vomiting. There is also the possibility for serious allergic skin reactions, such as Stevens- Johnson syndrome, a potentially fatal skin disorder. The more serious adverse effects of sulfonamides include blood dyscrasias, such as agranulocytosis, aplastic anemia, and thrombocytopenia, which may occur with long-term use of the medication in susceptible clients. Clients also are at risk for superinfections, such as Clostridium difficile-associated diarrhea (CDAD). Renal damage can occur from crystals formed in the urinary tract, so it is recommended that clients consume at least 1,200 mL/day of water. Kernicterus, a newborn disorder characterized by bilirubin deposits in the brain, can occur, so sulfonamides are not recommended for infants, pregnant or lactating clients. Interventions When caring for clients taking a sulfonamide antibiotic, monitor for and report severe gastrointestinal manifestations. Give medication with food if they experience nausea. Another important intervention is to monitor for and report any deficiencies of erythrocytes, leukocytes, or platelets. Like many broad-spectrum antibiotics, there is the possibility for superinfections such as severe diarrhea caused by C-diff. Also, monitor for and report any skin rash and hives, which may indicate an allergic reaction. If this happens, avoid giving any more doses until you consult with the provider. If the rash is severe and includes blisters, stop the medication and call the provider. Monitor I & O and encourage client to drink plenty of fluids. Monitor CBC and urinalysis frequently during treatment. Safety Alert Stevens-Johnson syndrome is a rare skin reaction that occurs secondary to certain medications such as NSAIDs, anticonvulsants, penicillins, and sulfonamides. The initial onset is fever and sore throat. It manifests itself as a painful, red-to-purple skin rash that spreads rapidly. It can also cause blisters on the skin and inside the mouth. The blisters will cause a sloughing of the skin, creating a means for infection. The infection leaves scars and irregular pigmentation after healing. When you see these reactions, understand that it is most important to immediately stop the offending medication. Cool moist compresses, antihistamines for itching, and analgesics for pain promote comfort during the acute phase. If the area of lesions is large, ensure that the client is getting adequate fluid replacement either orally, through IV, or both. If you identify this syndrome early, you can increase the clients' chances of stopping the reaction in its early stages. Then it does not get to the point where recovery takes months or involves the use of skin grafts to repair the damage. Administration Sulfamethoxazole and trimethoprim are available as a fixed-dose combination in tablets, liquid solution, and IV form. Give an oral dose with 8 oz of water and encourage the client to drink 1,200 to 1,500 ml of fluid per day during therapy. For an IV infusion, slowly administer sulfamethoxazole and trimethoprim via an intermittent IV over 60 to 90 min. While doing this, remember to follow the manufacturer's recommendations for dilution. Client Instructions When providing instructions, tell clients to drink at least 1,200 to 1,500 mL of water per day during sulfonamide therapy. Encourage them to take the medication with food to minimize gastrointestinal manifestations. If they do not experience any relief, tell them to call the provider. Also, tell clients that sulfonamides frequently cause allergic reactions. So, if a rash and/or hives develop, the client needs to stop taking the medication and immediately contact the provider. In regard to blood deficiencies, instruct clients to report fatigue, pallor, easy bruising, and any new infections, such as a sore throat. Remember, it is important to emphasize that clients report watery or bloody diarrhea, mouth pain, difficulty eating, or vaginal burning and discharge. Lastly, warn clients using oral contraceptives that sulfonamides can decrease their effectiveness. So, in the meantime, clients will need to use an alternate form of contraception. Contraindications and Precautions Do not give sulfonamides to women who are pregnant or nursing. Also, clients who are allergic to sulfonamides, trimethoprim, and cyclooxygenase-2 inhibitors, such as celecoxib, also called Celebrex, should not receive them. Clients with megaloblastic anemia resulting from folic acid deficiency should not receive sulfonamides. This also applies to children under the age of 2 months. Finally, clients with pharyngitis resulting from group A beta-hemolytic streptococci, hyperkalemia, or severe impairment in urine creatinine clearance, should not take these medications. When giving sulfonamides, use caution in clients who have a decrease in kidney or liver function or a hypersensitivity to sulfites that are a preservative in wine and food and to other medications that have chemical similarities to sulfonamides. These medications include acetazolamide, thiazide diuretics, and tolbutamide. Also, closely monitor clients with bone marrow suppression. Lastly, those clients at risk for megaloblastic anemia, namely clients who have alcohol misuse disorder, pregnant women, and clients with debilitation, need to only take sulfonamides if the benefits outweigh the risks. Interactions It is important to remember that sulfonamides, in combination with alcohol, may cause a disulfiram-like reaction, which is very unpleasant and possibly dangerous. These medications may also increase the effects of warfarin and phenytoin, tolbutamide, and oral antidiabetic medications, such as sulfonylurea. When clients take sulfonamide with methotrexate, they may experience an increase in immunosuppression. An important interaction to remember when providing client instructions is that sulfonamides reduce the effectiveness of oral contraceptives. Clients need to use an alternative form of contraception during therapy and until the next menstrual cycle begins. Since sulfonamides are frequently used to treat urinary tract infections, which are common in clients of childbearing age, it is important to remind clients who are taking oral contraceptives to use an alternative form of birth control while taking this medication. Broad spectrum antibiotic Penicillin Interventions When caring for clients who are taking penicillin, it is important to monitor them for gastrointestinal manifestations. Mild manifestations may occur, so the client needs to take the medication with food. However, if the client reports several diarrhea stools a day that are watery and contain blood, expect Clostridium difficile to be found in stool samples. Report these manifestations immediately to the provider, who will probably stop the medication and initiate a different type of medication therapy for the colitis. Also, it is important to monitor and report Candida infections of the vagina and mouth. Vaginal infections with Candida cause intense itching and a white, cottage cheese-type discharge. Candida of the mouth is known as thrush.These oral infections from Candida cause severe pain and inflammation of the tissue. White patches on the oral mucosa are also common. Expect to treat Candida infections by using an antifungal agent. Remember, after administration, it is important to monitor clients for rash, hives, wheezing, and difficulty breathing. If this occurs, immediately notify the provider. Also, when giving intramuscular or intravenous penicillin, keep the client in the facility for 30 min after administration. Note that some clients are allergic to penicillin, with anaphylaxis occurring more frequently with penicillin than any other medication. Safety Alert Clients allergic to penicillin are at risk for anaphylactic shock if they take a penicillin-type medication. Before an initial dose, ask clients if they have ever had an allergic reaction to penicillin. Even if they had a reaction as a child, providers should not prescribe penicillin unless they receive a sensitivity test first. If clients do not remember having a reaction as a child, do a subdermal allergy test. This test places a very small amount of penicillin under the skin. If no reaction occurs, give a dose of penicillin. But observe clients closely for the manifestation of a reaction. If one occurs, give epinephrine and respiratory support. Administration Several preparations of penicillin come in an extended-release form. Make sure that clients do not crush or chew them before swallowing. There are chewable forms for children, however, who should chew them before swallowing. When giving penicillin drops to an infant or young child, place the drops on the child's tongue. Mixing them in a small amount of juice or formula is also acceptable. Remember, always be sure that the child takes the full dose. Some clients may prefer to take the medication at the beginning of their meals. This will decrease Gl manifestations and increase absorption. If probenecid is prescribed with amoxicillin, it will delay excretion by the kidneys. This will increase the therapeutic level of amoxicillin. Client Instructions If clients experience watery or bloody diarrhea, they need to report it immediately to the provider. Taking the medication at the start of meals will help reduce gastrointestinal distress. Also, they need to contact their provider if they experience mouth pain, an inability to eat, or vaginal burning, itching, and discharge. A rash and hives are other very important manifestations to report. If clients experience these, tell them to stop the medication and call the provider. If they are having trouble breathing, are wheezing, or their airway is swelling, they need to call 911. Contraindications and Precautions Clients who have had an allergic reaction to penicillin in the past should not take it. Those with hypersensitivity to procaine and benzathine should also not use this medication. Use cautiously in clients with severe renal impairment-the dose may need to be reduced. Interactions Probenecid increases the blood levels of penicillin, which can be therapeutic, or it can cause serious side effects. Concurrent use with bacteriostatic agents is generally not recommended Likewise, penicillin can reduce the effectiveness of oral contraceptives. Antibacterials-Cephalosporins Cephalosporins are beta-lactam, broad-spectrum antibiotics that are very similar in structure to penicillins. So, many of their uses and adverse effects are the same. The development of cephalosporins over the past several decades is helping to refine them. Categorization of them occurs in generations, starting with the first and ending with the fifth. Cephalexin, a first- generation cephalosporin, treats infections that gram-positive cocci cause. With the refining of cephalosporins, their effectiveness against gram-negative bacteria is increasing. Also, fewer bacteria are developing resistance against them. Later generations are also more capable of penetrating cerebrospinal fluid to treat infections like meningitis. Prototype and Other Medications The prototype medication for cephalosporins is cephalexin (a first-generation cephalosporin). Another first-generation medication is cefazolin. Second-generation medications include cefaclor, cefoxitin, and cefotetan. A third-generation medication is ceftriaxone. There is also cefotaxime. There are fourth-generation medications, including cefepime and cefiderocol. The last examples of cephalosporins are fifth-generation medications, ceftolozane and ceftaroline. Ceftaroline is administered IV and is the only cephalosporin with activity against methicillin- resistant Staphylococcus aureus (MRSA) associated infections. Expected Pharmacologic Action Cephalosporins weaken and destroy the cell walls of bacteria that are sensitive. They do this by inhibiting the enzyme necessary for cell-wall formation, transpeptidase. Then, they activate the enzyme that opens the cell wall during replication, autolysin. The combination of these actions weakens the cell wall and expedites the destruction of the bacteria. Since the cells of humans lack a cell wall, cephalosporins do not damage the host. So, they are extremely safe for administration. Cephalosporins are bactericidal against many aerobic gram-positive bacteria. Later generations are more effective than the first ones against aerobic gram-negative and anaerobic bacteria. Adverse Drug Reactions Even though cephalosporins are extremely safe for use, they do have adverse effects, and some of these can be extremely serious. Oral ingestion of cephalosporins may cause gastrointestinal manifestations such as diarrhea, nausea, and vomiting. Rarely, cephalosporins may cause Clostridium difficile-associated diarrhea (DAD) as the result of growth of Clostridium difficile (C.diff). While cephalosporins are relatively safe for use, they can cause an allergic reaction in clients who are sensitive. Clients who are allergic to cephalosporins will experience rashes and hives. This usually occurs within the first few days of therapy. If the reaction is severe, the client will experience swelling of the airway, wheezing, and difficulty breathing. Remember, these are manifestations of an anaphylactic reaction. Also, all clients who are prescribed cephalosporin need to be asked if they have ever had an allergic reaction to cephalosporin or penicillin. If they have, they will require another non-cephalosporin prescription. One cephalosporin, cefotetan, can increase a client's risk for bleeding and hemorrhage. It can also cause a disulfiram-like reaction when taken with alcohol. Thrombophlebitis is a potential side effect of IV cephalosporins. Interventions Clients taking cephalosporin require monitoring for bloody stools or watery diarrhea. If either occurs, notify the provider. Inform the provider if the client is allergic to either cephalosporin or penicillin. Even if the client denies an allergy, prepare to treat a severe allergic reaction or anaphylaxis with epinephrine, antihistamines, and respiratory support. If the client is receiving cefotetan, monitor the client's prothrombin time, or PT. You also need to monitor the international normalized ratio, or IN, and partial thromboplastin time, or PTT. These actions help you evaluate the potential for an increase in bleeding time. If bleeding occurs, administer vitamin K. During an IV infusion of any cephalosporin, you need to monitor for thrombophlebitis. If it develops, stop the infusion, and change the IV site. Follow recommendations for diluting IV cephalosporins. They must infuse slowly over a time frame that is specific for that cephalosporin. Monitor renal function tests, such as the blood urea nitrogen (BUN) and creatinine. You can expect clients to be on a smaller dose of cephalosporins if their laboratory values indicate renal insufficiency. Finally, do not forget to inform the client about the potential for a disulfiram-like reaction. This occurs if cefotetan is taken with alcohol. Safety Alert Broad-spectrum antibiotics such as cephalosporins not only kill the bad bacteria that cause infection, but they also kill good bacteria in the intestine. This causes an overgrowth of Clostridium difficile. This causes severe diarrhea and can evolve into a life-threatening inflammation of the colon. Dehydration and bleeding may also occur along with rupture of the colon and kidney failure. Clients should stop taking the medication immediately and receive treatment for the infection. Antibiotics such as metronidazole or vancomycin are the medications of choice. Administration Cephalexin is available as capsules, tablets, or as an oral suspension. It is not available in an injectable form. Other cephalosporins may be available for both oral and injectable use. Carefully differentiate between cephalosporin prescriptions because their generic names are very similar. For example, cefoxitin is a second-generation medication, and cefotaxime is a third-generation medication. Cefepime is a fourth-generation medication. Client Instructions Remember to tell clients that cephalosporins may cause watery or bloody diarrhea. If either happens, they need to contact their provider immediately. Encourage them to take the medication before meals to help with gastrointestinal distress. If they experience a rash or hives, they need to stop the medication, as these are manifestations of an allergic reaction. Difficulty breathing, wheezing, or swelling of the airway requires an immediate call to 911. Clients taking cefotetan need to report any unusual bruising and bleeding to the provider. Also, inform them that nausea, vomiting, severe headache, and hypotension may occur if the medication is taken with alcohol. Clients receiving the medication by IV need to report any burning, pain, or swelling at the site. Contraindications and Precautions Contraindications for clients taking cephalosporins include an allergy to cephalosporin antibiotics or those with serious hypersensitivity to penicillins. Clients with a carnitine deficiency should not take cefditoren because it causes an increase in the excretion of carnitine. Also, clients with a milk-protein allergy should avoid this medication because tablets contain sodium caseinate, a protein found in milk. Clients taking cefotetan should avoid alcohol because it may cause a disulfiram-like reaction. This reaction resembles one that clients with alcohol use disorder experience when they are taking the anti-alcohol medication disulfiram with alcohol. Clients may experience nausea, vomiting, severe headaches, and hypotension. Use caution when giving cephalosporins to clients with renal failure or gastrointestinal disease. Interactions Like penicillins, probenecid prolongs the effects of most cephalosporins. Cefotetan in combination with alcohol or other medication prolongs and promotes bleeding. The combination of IV calcium and ceftriaxone causes a precipitate to occur. This can lodge in the lungs and kidneys, causing damage. Antibacterial - Vancomycin Vancomycin is an antibiotic that does not contain a beta-lactam ring. So, its primary use is for gram-positive infections, methicillin-resistant Staphylococcus aureus (MRSA) infections, and Clostridium difficile, the offending organism in membranous colitis. Vancomycin is also an alternative for clients who are allergic to penicillin. Prototype and Other Medications Medication Classification-Anti-infective The medication, vancomycin, is the prototype and only medication in this category. Expected Pharmacologic Action The bactericidal action of vancomycin weakens and destroys the cell walls of bacteria. It does this by inhibiting the enzyme, transpeptidase, which is necessary for cell-wall formation. It also activates the enzyme, autolysin, which opens the cell wall during replication. Vancomycin is effective against gram-positive bacteria and MRSA infections. It also targets the organism in membranous colitis, Clostridium difficile. Adverse Drug Reactions It is important to recognize the adverse effects of vancomycin. The major toxic concern is renal failure, which should be monitored frequently with trough concentration levels and periodic assessment of serum creatinine levels. Other adverse reactions include tachycardia, hypotension, rash, pruritus, urticaria, and flushing of the face and trunk, which can occur when an IV infuses too rapidly. These effects are collectively known as a vancomycin infusion reaction and are thought to be related to a rapid release of histamine. Ototoxicity is rare and is normally reversible. The dose for vancomycin is calculated to the client's weight. This prevents the client from receiving a higher dose. Vancomycin is very irritating to the veins, so thrombophlebitis at the IV site is common. Dilute it, give it slowly, and change IV sites frequently. This prevents damage to the vein. Evaluate the IV site prior to administration of vancomycin. Also, be sure to evaluate the IV site prior to intravenous administration of vancomycin to prevent tissue damage from extravasation secondary to an infiltrated IV. Interventions As with any other anti-infective, clients should be monitored for anaphylaxis as well as manifestation of superinfections. When administering vancomycin by IV, infuse for over 60 min or longer. Also, follow the recommendations for dilution. As the IV is infusing, monitor the client's vital signs and watch for a vancomycin infusion reaction. To prevent ototoxicity and nephrotoxicity, closely monitor vancomycin blood levels. If any are above the therapeutic range, call the provider. Lastly, always monitor the IV site for redness and swelling. This indicates phlebitis. So, ensure that the IV is patent before and during the infusion. Administration When administering vancomycin orally, mix it with flavoring syrup to mask the unpleasant taste. When giving the medication for Clostridium difficile infections, anticipate giving it orally, as this is the only manner in which it will be effective for this infection. For all other infections, give vancomycin by IV. Again, give it slowly and follow the recommendations for dilution. Vancomycin is extremely incompatible in combination with other medications. So, use a multi-lumen IV catheter or designate an IV line for it. Client Instructions Because IV vancomycin is usually given to clients in acute care settings, instruct them to report facial flushing and feelings of faintness during infusion. Also, clients need to immediately report pain, swelling, or redness at the IV site. Oral vancomycin administration should include instructions to the client to finish all medication and report tinnitus, vertigo, and hearing loss. Safety Alert Renal failure is a serious adverse effect of vancomycin. The risk to the client is dose-related and is compounded by the concurrent use of other medications that are nephrotoxic. Monitor lab work as indicated above. Always administer vancomycin IV over a minimum of 60 min to avoid other adverse effects discussed above. Contraindications and Precautions Avoid giving vancomycin to clients who are hypersensitive to the medication. Also, use caution when giving it to those with renal insufficiency. If giving vancomycin to clients with renal insufficiency, reduce their dosage and begin monitoring peak and trough levels. It is also vital to monitor their kidney function frequently. Understand that clients with a hearing impairment should only take vancomycin if its benefits outweigh its risks. Clients with a diagnosis of colitis or inflammatory disorder of the colon should only take vancomycin after much consideration. Interactions When giving ototoxic or nephrotoxic medications (aspirin, aminoglycosides, cyclosporines, loop diuretics) with vancomycin, there is an increase in the risk for ototoxicity or nephrotoxicity. It is also incompatible with other IV antibiotics, as well as multiple other IV medications. So, do not mix vancomycin with any other medications or give it through the same IV line as another medication. Use a multi-lumen catheter or designate an IV line for it so it does not mix with other IV medications during administration. Isoniazid Isoniazid treats both active TB and latent TB. Clients with latent TB are those who demonstrate a positive TB skin test but do not have the active form of the disease. Prototype and Other Medications Medication Classification-Antitubercular Isoniazid is the prototype medication. Its abbreviation is INH. Other first-line medications that treat tuberculosis are pyrazinamide, abbreviated as PZA, ethambutol, and rifampin. New clinical guidelines for treating TB were issued in 2016 by the CDC, the American Thoracic Society, and the Infectious Diseases Society of America. Various treatment regimens are recommended based on the condition of the client and the infecting organism. Expected Pharmacologic Action Research suggests that isoniazid interferes with lipid, RNA, and DNA synthesis in tubercle bacilli, thus inhibiting mycobacterial cell wall synthesis. It is also bacteriostatic and acts specifically on tubercle bacilli. In higher doses, it can be bactericidal. Adverse Drug Reactions Hepatotoxicity and liver damage, including hepatitis and liver failure, are concerns with isoniazid therapy, especially in older clients and clients who have alcohol use disorder. Peripheral neuropathy, which manifests as numbness, tingling, and pain in the hands or feet, is another concern, primarily for clients with diabetes or alcohol use disorder. This side effect has ties to pyridoxine, or vitamin B6 deficiency, which isoniazid therapy can precipitate. The neuropathy is reversible with supplemental vitamin B6 therapy, and clients who are at risk, such as those with diabetes, may take this supplement at the beginning of their therapy. CNS side effects may occur and are often dose-related. These include dizziness, ataxia, seizures, and psychotic manifestations. Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) may occur, which resembles an acute viral infection. See interventions below. Adverse effects of isoniazid occasionally include gastrointestinal manifestations such as nausea and vomiting. Interventions When caring for clients taking isoniazid, it is important to monitor for the manifestation of DRESS (fever, rash, lymphadenopathy, and/or facial swelling associated with involvement of other organ systems (hepatitis, nephritis, hematologic abnormalities, myocarditis, myositis); therapy should be stopped if manifestations appear. Also, monitor for and report gastrointestinal manifestations. This is important because they will take the medication on a regular basis for several months. Observe manifestations of liver damage such as jaundice, abdominal pain, and an unusual level of fatigue. Administer pyridoxine, vitamin B6, to treat or prevent neuropathy. Continually monitor the client for CNS manifestations, and report these when necessary. Monitor the liver enzyme levels of clients during therapy. This makes early manifestations of hepatotoxicity recognizable. Safety Alert Isoniazid can be hepatotoxic or toxic to the liver. This happens more in older clients, clients who consume excessive amounts of alcohol, or those with a preexisting disorder of the liver. So, it is very important to monitor clients' aspartate aminotransferase, or AST, and alanine aminotransferase, or ALT, monthly to check for elevations. These enzymes measure liver function. An increase in their values over time can indicate that liver toxicity is occurring. Observe for jaundice, yellowing of the sclera and skin, darkening of the urine, and reports of fatigue, anorexia, nausea, and vomiting. Administration Give isoniazid as either a tablet or as oral syrup. Set-dose combination tablets or capsules that also contain rifampin are available. Intramuscular administration of isoniazid is rare, but when it is done, be sure to administer it in a large muscle mass and rotate sites. If the IM solution contains crystals, warm it to room temperature before injecting it. Also, anticipate giving isoniazid with one or more medications for active TB. This helps prevent resistance. And when giving isoniazid for latent TB, it is usually a single medication, which the client will take for 6 to 9 months. Emphasize the importance of compliance for enhancing the effectiveness of the medication therapy. Client Instructions It may be taken with or without food, but avoid taking within 1 hr of antacids containing magnesium. Describe to clients what jaundice looks like, and instruct them to report yellowing of the skin or sclera, abdominal pain, and an unusual level of fatigue. Reinforce the need for them to also report numbness, tingling, and pain in the hands and feet. This is especially important for clients with diabetes mellitus. Remember to warn clients about CNS manifestations that require notification of the provider. Emphasize the importance of compliance for enhancing the effectiveness of the medication therapy. Contraindications and Precautions Do not give isoniazid to clients who are allergic to it. Also, clients with a history of liver damage from isoniazid should not take it a second time. Lastly, never give it to clients with severe liver damage. Remember to use caution when giving isoniazid to clients who are over 50. Precautions also need to be taken for clients who have chronic liver disease, including hepatitis, and those who have alcohol use disorder, HIV, or a seizure or renal disorder. Interactions Remember that drinking alcohol while receiving isoniazid therapy will increase the risk of toxicity and adverse reactions. It can also stimulate a disulfiram-like reaction, psychosis, or ataxia. Giving isoniazid with phenytoin may cause phenytoin toxicity. Antacids containing aluminum will decrease the absorption of isoniazid. There are two other TB medications, ethionamide and cycloserine, that can increase the incidence of CNS toxicity in some clients. Rifampin Rifampin is another antituberculosis medication that you give as an adjunct to another antituberculosis medication, such as isoniazid. Unlike isoniazid, it is not specific to the tubercle bacilli. It also can treat leprosy and prevent Haemophilus influenzae infection. It is also effective against N. meningitidis the organism that causes meningococcal meningitis, Legionella (responsible for Legionnaires disease) and Staphylococcus aureus. E Prototype and Other Medications Medication Classification-Rifamycins(Antitubercular) Rifampin is the antimycobacterial medication Expected Pharmacologic Action Rifampin, a broad-spectrum antibiotic, suppresses protein synthesis by inhibiting the action of RNA polymerase. It is bacteriostatic and bactericidal to sensitive bacteria. Rifampin is effective against gram-positive and gram-negative bacteria. It is also effective against the organisms responsible for leprosy (Mycobacterium leprae) and meningitis (N. meningitidis), and others as noted above. Adverse Drug Reactions Adverse effects of rifampin include liver toxicity, which can develop into hepatitis. The urine, saliva, tears, and sweat of clients may turn red-orange. This may startle clients, but it is harmless. And, like most antibiotics, gastrointestinal symptoms such as nausea, vomiting, diarrhea, cramping, and abdominal pain can occur. Flushing, rash, and itching may also occur. Interventions When caring for a client who is taking rifampin, monitor their liver enzyme levels throughout therapy. If you find any alterations or manifestations of hepatitis, such as abdominal pain, nausea,an unusual level of fatigue, or jaundice, be sure to report them. It is important to monitor for manifestation of DRESS (fever, rash, lymphadenopathy, and/or facial swelling), associated with involvement of other organ systems (hepatitis, nephritis, hematologic abnormalities, myocarditis, myositis); therapy should be stopped if manifestations appear. Monitor the client's urine, saliva, tears, and sweat for discoloration, and assure them that it is a harmless side effect. Tears may also stain contact lenses. Finally, remember to monitor clients for persistent gastrointestinal manifestations. Report these, as they may jeopardize compliance with the medication regimen. Administration Rifampin is available in capsules and in fixed-dose combinations of capsules or tablets that contain isoniazid. Expect to give rifampin with other TB medications to prevent medication resistance. Give oral doses of rifampin 1 hr before or 2 hr after meals, unless gastric distress is problematic. Rifampin may be taken with food, but its absorption will decrease. Rifampin is available in an IV injection form, which needs to be given according to the manufacturer's recommendations for dilution and rate. Client Instructions Clients taking rifampin as part of their antimycobacterial therapy for TB need to report abdominal pain, nausea, and an unusual level of fatigue or jaundice. These manifestations may indicate that liver damage is occurring. Warn clients that discoloration in their urine, saliva, tears, and sweat may occur. When talking to clients who wear soft contact lenses, tell them that their tears may stain the lenses. Encourage them to discuss this issue with their ophthalmologist, who may prescribe lenses that are worn only once a day. If taking rifampin with food does not control a client's gastrointestinal manifestations, tell them to call the provider. Remember to tell clients of childbearing age that rifampin can adversely affect the effectiveness of oral contraceptives, so they need to consult with their provider for another form of birth control to prevent pregnancy.Instruct clients not to ingest alcohol while on this medication. Safety Alert Clients taking an oral contraceptive, especially a low-dose hormone contraceptive, should consider using a second form of contraception or changing to a nonhormonal contraceptive if the medication is to be taken on a long-term basis. Contraindications and Precautions Contraindications to taking rifampin include an allergy to it. Take precautions when giving it to clients who have a history of liver disease, alcohol use disorder, diabetes, or who are receiving other hepatotoxic medications. Interactions Rifampin decreases the blood levels of oral contraceptives, warfarin, and several medications for HIV, particularly protease inhibitors. Concurrent administration of rifampin with isoniazid and pyrazinamide will increase clients' risk for liver toxicity because all three are hepatotoxic medications. However, when weighing the risk of a client developing medication-resistant TB, these medications are usually given together. Then, monitor the client closely for a change in liver enzymes. Metronidazole Metronidazole is a broad-spectrum azole antibiotic. Its oral form treats both bacterial and protozoal infections. For example, it treats bacterial infections such as Clostridium difficile- associated diarrhea (DAD), which occurs secondary to broad-spectrum antibiotic use and bacterial vaginal infections. For protozoal infections, it treats infections such as intestinal and systemic amebiasis, giardiasis, and trichomoniasis, in both males and females. The IV form helps to prevent anaerobic bacterial infections, such as in colorectal, abdominal, and vaginal surgeries. You can also use metronidazole in combination with tetracycline and bismuth subsalicylate for Helicobacter pylori, which is a cause of peptic ulcer disease. E Prototype and Other Medications Medication Classification-Anti-infective, antiprotozoal, antiulcer agents Metronidazole is the prototype medication for various protozoal infections. Other antiparasitic medications include tinidazole (another broad-spectrum antiprotozoal), ivermectin (tissue nematodes and scabies), and permethrin (lice). Expected Pharmacologic Action Metronidazole damages the DNA in anaerobic organisms. It is unique because it does not produce a pharmacologic action until it is inside the anaerobic organism. Then, it damages the DNA inside it, interfering with its ability to replicate. Metronidazole is also bactericidal against anaerobic gram-negative bacteria and various types of protozoa. Adverse Drug Reactions The most common adverse effects of metronidazole are gastrointestinal manifestations of nausea, vomiting, and diarrhea, as well as anorexia and dry mouth. Some clients experience a metallic taste in their mouth, which can affect their appetite. Clients may also experience mild to moderate CNS manifestations, which include headache, vertigo, and ataxia. The more severe manifestations include seizures and peripheral neuropathy. The latter two manifestations rarely occur, but when they do, stop the medication. A harmless side effect of metronidazole is the darkening of urine. Interventions When caring for a client, monitor for and report severe Gl manifestations. Give metronidazole with food or milk to help minimize gastric distress. Monitor them for and report CNS manifestations. Monitor neurological status and stop the medication if the client begins to experience seizures or neuropathy. Advise clients that a discoloration in their urine may occur. But this should not concern them. Administration Metronidazole is available as tablets, capsules, sustained-release capsules, topical cream, vaginal gel, and IV infusion. When giving the IV form, reconstitute it from powder and dilute it according to the manufacturer's recommendations so that it can infuse slowly. Clients must swallow the sustained-release form whole and not crush or chew it. Clients may crush regular tablets if they cannot swallow them. Giving oral doses 1 hr before or 2 hr after a meal will provide for the best absorption of the medication. However, clients can take metronidazole with food or milk if gastric distress is a concern. Client Instructions Instruct clients to take metronidazole just before, with, or after a meal if gastrointestinal manifestations occur. If the manifestations are severe, they need to call their provider, who may change the prescription. Instruct clients that they may experience a metallic taste as well as dizziness and headaches. Inform them about potential CNS manifestations, such as numbness or paresthesia of the extremities. Be sure to inform them about the discoloration of their urine. which should not be alarming. Contraindications and Precautions Avoid giving metronidazole to clients who have an active CNS disease or severe blood disorder, as well as those who are pregnant. Also, use caution in clients who have a history of blood dyscrasias, heart failure, liver or renal failure, or a seizure disorder. Interactions Metronidazole reacts with several types of medications. If given in conjunction with citalopram, ritonavir, or IV forms of nitroglycerin, sulfamethoxazole, or trimethoprim, the client can experience a disulfiram-like reaction. For clients taking disulfiram as a part of their treatment for alcohol use disorder, the addition of metronidazole may cause a psychotic reaction. Phenobarbital decreases blood levels of metronidazole, but metronidazole increases lithium levels. Fluorouracil and azathioprine may cause temporary neutropenia and increase a client's risk for infection. When giving metronidazole by IV, remember that it has multiple solution incompatibilities with other IV medications, so infuse it through a separate lumen. Also, designate a separate IV line for it. Drinking alcohol while taking metronidazole causes a very uncomfortable disulfiram-like reaction. Safety Alert Clients who have alcohol use disorder who wish to avoid the ingestion of alcohol take disulfiram. While it does not cure alcohol use disorder, it causes adverse effects that discourage drinking. If clients consume alcohol while taking disulfiram, they can experience facial flushing, nausea, vomiting, hypotension, sweating, shortness of breath, dizziness, and anxiety. For most clients, this reaction lasts about an hour and causes extreme discomfort. For other clients, this reaction can cause shock. Put supportive measures in place until the effects subside. Disulfiram-like reaction, means that an interaction between another medication and alcohol or two separate medications can cause a similar type of reaction. Inform clients about this reaction when they start taking this medication and advise them to avoid the consumption of alcoholic beverages or products containing alcohol.