BSN210 Clinical Pharmacology - Respiratory & Antibacterial Drugs PDF

CLINICAL PHARMACOLOGY BSN210 Drugs for Respiratory Conditions & Antibacterial Academic Year 2024-2025 Semester 1...

CLINICAL PHARMACOLOGY BSN210 Drugs for Respiratory Conditions & Antibacterial Academic Year 2024-2025 Semester 1 Week 11 BSN210 Clinical Pharmacology fchs.ac.ae  Session Learning Outcomes At the end of the lecture, the student should be able to: List the common names, actions, possible side effects, and adverse effects of bronchodilators, anti-inflammatory, antibacterial, and mucolytic drugs for respiratory problems. Describe what to do before and after giving bronchodilators, anti-inflammatory, mucolytic, and antibacterial drugs. Explain what to teach patients taking bronchodilators, anti-inflammatory, mucolytic, and antibacterial drugs, including what to do, what not to do, and when to call the prescriber. 2 fchs.ac.ae  Introduction The respiratory system is subject to numerous conditions that interfere with respiration and lung function, including: 1. Conditions that obstruct airflow (e.g. Asthma and chronic obstructive pulmonary disease (COPD) 2. Allergic disorders 3. Inflammatory disorders 4. Respiratory Tract Infections 3 fchs.ac.ae 4 fchs.ac.ae  Drugs Acting on the Respiratory System The goal of drug therapy for asthma & COPD: 1. Reduce symptoms & Improve airflow. 2. Prevent asthma attack, slow COPD progression Controller drugs: to prevent an attack from starting. Rescue drugs: to reduce attach severity or stop it. Most drugs used to treat COPD are the same as those used to treat asthma, although the dose, route, timing may differ. 5  Types of Inhalation Devices There are various types of inhalation devices: Metered-dose inhalers (MDIs) § It is a handheld device that disperses medication through aerosol spray or mist to penetrate lung airways. § Pressurized devices that deliver a measured dose of drug with each activation. § Hand-mouth coordination is required 6 fchs.ac.ae  Types of inhalation devices qSpacers: § Use with MDIs § Increase delivery of drug to the lungs & decrease deposition of drug on the oropharyngeal mucosa. § Especially important for inhaled corticosteroids. 7 fchs.ac.ae  Types of Inhalation Devices Dry-powder inhalers (DPIs) § Drugs are in the form of dry, micronized powder. § Breath activated, much easier to use. § DPIs deliver medication to the lungs as patients inhale through the device. The DPI doesn’t push the medication into your lungs. 8 fchs.ac.ae  Types of inhalation devices Nebulizers § Small machine to convert a drug solution into mist. § Droplets in the mist are much finer than those produced by inhalers. § Administered through face mask or mouthpiece held between the teeth. § Take several minutes to deliver the same amount of drug contained in 1 puff from an inhaler. 9 fchs.ac.ae  Common Problems: Inhalers 1. Patients not taking the medication as prescribed (Too much, too low) 2. Incorrect activation: pressing canister & breath should be done simultaneously. 3. Forgetting to shake the MDI (may not deliver the correct dose), Do not shake DPI (medication may spill out). 4. Not waiting long enough between puffs (whole process should be repeated). 5. Failure to clean the valve (particle may jam up the valve). 6. Failure to observe whether inhaler is actually releasing a spray. 10 fchs.ac.ae  Categories of Drugs Acting on the Respiratory System Drugs that act on the respiratory system include: I. Bronchodilators. II. Anti-inflammatories. III. Mucolytics IV. Corticosteroids. V. Leukotriene receptor antagonists. 11 fchs.ac.ae  I. Bronchodilators Drugs used to relieve bronchospasms associated with respiratory disorders Includes: A. Beta 2 adrenergic agonists B. Cholinergic antagonists (Anticholinergic) Intended responses: Pulmonary smooth muscle relaxation (have no effects on inflammation) Airway widening, allow air to move freely in & out alveoli. Decreasing wheezing (disappears) 12  A. Beta2-adrenergic Agonists Bind to the beta2 receptors and cause increase in the production of substance (cAMP) that triggers pulmonary smooth muscles relaxation. They are divided into short-acting & long acting Short-acting beta2 adrenergic agonists (SABAs): Rescue drug Long-acting beta2 adrenergic agonists (LABAs): Controller Drug type SABAs (rescue drug) LABAs (controller drug) Action Rapid and short term relief. Need more time to build up an effect. Delivered to the lung, systemic Have no value on acute attack. effects are minimal. For Asthma Useful when asthma attack begins Used to prevent asthma attack For COPD When patient feel more breathless Taken daily to maintain open airway than usual Example albuterol (Apo-Salvent) salmeterol (Serevent) 13  B. Cholinergic antagonists (Anticholinergic) Blocks the parasympathetic nervous system. This allows a person’s natural epinephrine and norepinephrine to bind to smooth muscle receptors: bronchodilator effect. These inhaled drugs also bind to mucus membrane receptors and decrease airway secretion. They are prevention drugs & must be taken on a daily basis to prevent asthma & reduce airway blockage in COPD. Example: ipratropium (Atrovent) 14  I. Bronchodilators: Side effects: Inhaled bronchodilators have few side effects (dry mouth, bad taste in mouth) unless it is heavily used (can cause systemic effects). Systemic effect of bronchodilators: Rapid heart rate. Increase Blood pressure Feeling of nervousness. Difficulty sleeping Anticholinergic agents if they reach the bloodstream can cause: * Urinary retention. * Blurred vision * Eye pain * Nausea & headache 15  I. Bronchodilators: Adverse effects: Some brands of bronchodilators contain a preservative that causes minor to severe allergic reactions. patients should be checked for rashes, chest pain, and lightheadedness a few minutes after using the inhaler. Instruct the patient not to use their inhaler more frequently than prescribed, as it may cause angina or heart attack. 16  Bronchodilators: Nursing Alerts Pre administration: listen to the lungs (then compare) Take vital signs, check peak flow, and assess mental status. Post Administration: Check breathing status (↓RR, ↓ or absent wheeze, peak flow, O2 saturation o f 9 5% or higher usually occurs within 5 minutes of inhalation of short-acting bronchodilators). Compare pt’s HR, and BP within 15 min after giving the drug, and ask about chest pain, or restlessness. 17  II. Anti-Inflammatory Drugs Anti-inflammatory drugs: reduce inflammation but do not cause bronchodilation. Anti-inflammatory drugs for Respiratory Problems include: A. Inhaled corticosteroids B. Mast cell stabilizers C. Leukotriene inhibitors 18  II. Anti-inflammatory drugs A. Corticosteroids: Used for prophylaxis of chronic asthma. Decrease the production of body chemicals that trigger inflammation. Inhaled corticosteroids can prevent inflammation in the respiratory tract and reduce inflammation that has already started. Increase the number of bronchial beta2 receptors & their responsiveness to beta2 agonists. Examples: Beclomethasone (QVAR) Budesonide (Pulmicort) Fluticasone (Flovent HFA) 19  Nursing Actions § Rinse mouth with water without swallowing after administration to reduce the risk of candidiasis. § If taking bronchodilators by inhalation, use bronchodilators several minutes before the corticosteroid to enhance application of the corticosteroid into the bronchial tract. 20 fchs.ac.ae  II. Anti-inflammatory drugs B- Mast cell stabilizers § Stabilize mast cells & prevent the release of Broncho constrictive & inflammatory substances when mast cells are confronted with allergens & other stimuli § Only for prophylaxis of acute asthma attacks. § Examples: cromolyn sodium (Intal Inhaler), nedocromil sodium (Tilade). Nursing Alerts: § Cromoglycates are for long-term prophylaxis, patients should administer them on a regular schedule & the full therapeutic effects may take several weeks to develop. § They are contraindicated in patients who are hypersensitive to the drugs. 21  II. Anti-inflammatory Drugs C- Leukotriene receptor antagonists: Act by suppressing the effects of leukotrienes – which are compounds that promote bronchoconstriction as well as eosinophil infiltration, mucus production & airway edema. Ø Help to prevent acute asthma attacks induced by allergens & other stimuli. ü Indicated for long-term treatment of asthma Leukotriene inhibitors: work in several ways. zileuton (Zyflo) prevents leukotriene production within WBCs. montelukast (Singular) & zafirlukast (Accolate) block leukotriene receptors on inflammatory cells. 22 fchs.ac.ae 23  Corticosteroids (Cont’d) q Side effects Ø Inhaled anti-inflammatory and inhaled mast cell stabilizers: cough, bad taste, dry mouth increased risk for oral infection (candida fungal infection known as thrush). q Adverse effects Ø Inhaled corticosteroids: § Candidiasis of the mouth or throat § Hoarseness § Can slow growth in children. § Adrenal suppression may occur in long-term, high-dose therapy. § Increases the risk of cataracts (clouding of the lens of your eye). 24 fchs.ac.ae  Pre and Post Anti-inflammatory Drug Administration and Education Pre anti-inflammatory drug administration: Inspect the patient’s mouth and throat for oral infection - “thrush” (white-colored patches). Post anti-inflammatory drug administration: Assess the patient taking leukotriene inhibitor for signs and symptoms of ↓ liver function (fatigue, itchy skin, & jaundice of skin & sclera) Remind the patient to use an anti-inflammatory inhaler at least 5 min after using an inhaled bronchodilator. Teach the patient to take drugs as prescribed even when symptoms are not present. Instruct patients to rinse their mouth after using the drug to minimize the bad taste & mouth dryness. Teach patients to check gums, mouth and throat daily for redness or white/cream patches. 25  III. Mucolytics Reduce the thickness of the mucus Allowing the mucus to move easily out of the airways. guaifenesin (Mucinex) is a systemic mucolytic that is taken orally. The major mucolytic drug for COPD is acetylcysteine (Mucomyst) (Orally or inhaled) It works by breaking the connection that holds protein & mucus molecules, resulting in thinner less sticky mucus that is easier to cough up and spit out. 26 fchs.ac.ae  Cough preparation: Mucolytics (cont’d) Acetylcysteine is most commonly delivered with a nebulizer face mask & oral route. Acetylcysteine has few side effects and has a very unpleasant odor which may cause nausea & vomiting. Acetylcysteine may be given IV as an antidote for acetaminophen Overdose, it can protect the liver and kidney from damage. Dosage q Acetylcysteine 100 mg two to four times daily 200 mg two to three times daily 600 mg once daily 27 Anti-Infectives: Anti-Bacterial Drugs 28 fchs.ac.ae  Antibacterial Therapy Bactericidal & Bacteriostatic Drugs: Bactericidal are antibacterial drugs that kill bacteria directly. Bacteriostatic are antibacterial drugs that prevent bacteria from reproducing until the body’s own WBCs & antibodies get rid of them. Spectrum of efficacy: It is a measure of how many different types of bacteria the drug can kill or prevent from growing. 1. Narrow spectrum antibacterial drug: drugs effective against only a few types of bacteria. 2. Extended spectrum antibacterial drug: effective against more types of bacteria. 3. Broad spectrum antibacterial drug: effective against a wide range of gram-positive and gram-negative bacteria. 29 fchs.ac.ae  Antibacterial Therapy For selecting the appropriate antibacterial drug, it is important to identify the type, shape, and gram stain of bacteria. Culture & Sensitivity (C&S): this is the most common method. Culturing: transferring bacteria from the infected site and placing it in sterile nutritional broth to grow will then be examined microscopically. Sensitivity: place the disc with an antibacterial drug in the culture, if it does not grow, that means this drug is effective. 30 fchs.ac.ae  1. Penicillin Therapeutic Uses Penicillins: q Prevention and treatment of infections penicillin G, caused by susceptible bacteria, such amoxicillin, as: penicillin V potassium, Ø gram-positive bacteria ticarcillin/clavulanate, Ø Streptococcus, Ø Enterococcus, Ø Staphylococcus species 1. Any patient taking a penicillin should be carefully monitored for an Nursing allergic reaction for at least 30 minutes after its administration. 2. The effectiveness of oral penicillin is decreased when taken with Implication caffeine, citrus fruit, cola beverages, fruit juices, or tomato juice. fchs.ac.ae § Bacteria produce enzymes capable of destroying penicillin. These enzymes are known as beta-lactamase. As a result, the medication is not effective. Therefore, Chemicals have been developed to inhibit these enzymes: Clavulanic acid Tazobactam Sulbactam § These chemicals bind with beta-lactamase and prevent the enzyme from breaking down the penicillin qExamples of Penicillin-beta-lactamase inhibitor combination drugs: amoxicillin + clavulanic acid = Augmentin piperacillin + tazobactam = Zosyn fchs.ac.ae  2. Cephalosporins § Cephalosporins are bactericidal (kill bacteria) and work in a similar way to penicillin. § Divided into groups according to their antimicrobial activity o 1st generation cephalosporins: are effective against most common Gm(+) and Gm(-) bacteria. Examples: cephalexin (Keflex), cefazolin (Ancef). o 2nd generation cephalosporins: have increasing activity against Gm(-) bacteria. Example: cefuroxime (Ceftin). o 3rd generation cephalosporins: Most potent group against Gm(-) Less active Gm(+) bacteria. Examples: ceftriaxone (Rocephin), cefotaxime (Claforan). o 4th generation cephalosporins: Newest cephalosporin agents. o Broader spectrum of antibacterial activity than third generation, especially against gram- positive bacteria. o Example: cefepime (Maxipime). fchs.ac.ae q Cephalosporins are the drugs of choice for infections caused by Klebsiella pneumonia q Used for difficult-to-treat organisms such as Pseudomonas q Used prophylactically for Surgical prophylaxis for abdominal or colorectal surgeries q Respiratory Infections q Urinary Tract Infections 1. Orally administered forms should be given with food to Nursing decrease GI upset, even though this will delay absorption. Implication 2. Some of these agents may cause vomiting when taken with alcohol. fchs.ac.ae  3. Aminoglycosides Therapeutic Uses Nursing Implication § Used to kill gram-negative Monitor to prevent nephrotoxicity bacteria such as Pseudomonas., and ototoxicity. E. coli, Proteus., Klebsiella. § Often used in combination with Symptoms of ototoxicity include other antibiotics for synergistic dizziness, tinnitus, and hearing loss. effect. Symptoms of nephrotoxicity include § The most common (systemic): urinary casts, proteinuria, and n amikacin (Amikin) increased BUN (Blood Urea Nitrogen) n gentamicin (Cidomycin) and serum creatinine levels. n streptomycin fchs.ac.ae  4. Tetracyclines § Bacteriostatic drugs that inhibit bacterial protein synthesis. Discoloration of permanent teeth and tooth enamel in fetuses and children. § Administered orally, Thus, dairy products, antacids, and iron salts reduce absorption of tetracyclines Alteration in intestinal flora may result in: § Tetracyclines are contraindicated during Superinfection (growth of nonsusceptible pregnancy, and in children < age 8. organisms such as Candida) Diarrhea § Examples: n doxycycline (Adoxa) n tetracycline (Tetracon) n Minocycline (Minocin) fchs.ac.ae  5. Sulfonamides § Bacteriostatic drugs that inhibit Nursing Implication bacterial folic acid synthesis. § Should be taken with at least 2400 mL § Trimethoprim + sulfamethoxazole of fluid\day, unless contraindicated. (Bactrim) has a broad antibacterial spectrum and many indications § Due to photosensitivity, avoid sunlight n Examples and tanning beds. n sulfadiazine n sulfisoxazole (Gantrisin) § These agents reduce the effectiveness of oral contraceptives. fchs.ac.ae  6. Macrolide Antibiotics § Bacteriostatic drugs that are effective with oral administration. § erythromycin (Erymax) is often used in penicillin-allergic patients. § azithromycin (Zithromax) and clarithromycin (Biaxin) have a broader antibacterial spectrum and clinical uses. § Adverse effects include heartburn, rashes, and GI disturbances Nursing Implications § The absorption of oral erythromycin is enhanced when taken on an empty stomach, but because of the high incidence of GI upset, many agents are taken after a meal or snack. fchs.ac.ae  7. Fluoroquinolones\Quinolones § Bactericidal drugs that inhibit an enzyme essential to the function of bacterial DNA § Administered orally (Excellent oral absorption) § Absorption reduced by antacids § First oral antibiotics effective against gm(-) bacteria § Contraindicated in pregnancy and young children fchs.ac.ae  Nursing Implication Quinolones: Therapeutic Uses q Lower respiratory tract infections § Should be taken with at least 3 L of q Bone and joint infections fluid per day, unless otherwise q Infectious diarrhea specified q Urinary tract infections § Avoid exposure to sun q Skin infections § Not to be given with theophylline q Sexually transmitted diseases Examples § ciprofloxacin (Cipro) § moxifloxacin (Avelox) § ofloxacin (Floxin) fchs.ac.ae  What to do before giving antibacterial drugs 1. Check the patient’s blood urea nitrogen (BUN) and creatinine because aminoglycosides are toxic to the kidneys. 2. Check to see if patients also taking digoxin or warfarin because macrolides change the metabolism of these drugs, which can cause adverse effects. 3. Food, antacids, and dairy products prevent oral tetracycline from being absorbed. 41 fchs.ac.ae  What to do after giving antibacterial drugs 1. Ask patient about number of daily bowel movements and their character. 2. When giving the first dose of antibacterial drug , check the Patient every 15 minutes for any signs or symptoms of an Allergic reaction (hives at the IV site, low BP, rapid irregular Pulse, swelling of lips or lower face, the patient feeling lump In the throat) 3. Check IV site at least every 2 hrs for phlebitis (redness, pain, feeling of hard “cordlike” veins above the site - if this occur remove the IV access). 4. If the patient has anaphylactic reaction, your first priority is to prevent any more drug from entering him, stop the drug infusion. 5. Monitor patient for effectiveness of antibacterial drugs, check S&S of resolving infections. 42 fchs.ac.ae  Drug list for Respiratory Name of the Drug Classification beclomethasone (QVAR) budesonide (Pulmicort) Anti-inflammatory (Corticosteroid) fluticasone (Flovent HFA) cromolyn sodium (Intal Inhaler) Anti-inflammatory (Mast cell stabilizers) nedocromil sodium (Tilade) zileuton (Zyflo) montelukast (Singulair) Anti-inflammatory (Leukotriene receptor antagonists) zafirlukast (Accolate) guaifenesin (Mucinex) Mucolytics acetylcysteine (Mucomyst) albuterol (Apo-Salvent) Short-acting beta2 adrenergic agonists salmeterol (Serevent) Long-acting beta2 adrenergic agonists ipratropium (Atrovent) Cholinergic antagonists (Anticholinergic) BSN210 Clinical Pharmacology fchs.ac.ae  Drug list for Antibacterial Name of the Drug Classification cephazolin (Ancef) 1st generation cephalosporins cephalexin (Keflex) cefuroxime (Ceftin) 2nd generation cephalosporins cefotaxime (Clafotan) 3rd generation cephalosporins ceftriaxone (Rocephin) cefepime (Maxipime) 4th generation cephalosporins gentamicin (Cidomycin), amikacin (Amikin), streptomycin Aminoglycosides doxycycline (Adoxa), tetracycline (Tetracon), minocycline Tetracyclines (Minocin) sulfadiazine Sulfonamide azithromycin (Zithromax) Macrolides ciprofloxacin (Cipro), moxifloxacin (Avelox), ofloxacin Fluoroquinolones/quinolones (Floxin) BSN210 Clinical Pharmacology fchs.ac.ae  References Burchum, J. R., & Rosenthal, L. D. (2024). Lehne’s pharmacology for nursing care (12th ed.). Elsevier Saunders. Workman, M. L., & LaCharity, L. (2023). Understanding Pharmacology: Essentials for Medication Safety (3rd ed.). Elsevier Saunders. fchs.ac.ae