Week 9 GI System Drugs Notes PDF

# Week 9: GI System Drugs – very safe drugs ## 3 Specific Zones of Stomach and Different Glands 1. Cardiac - Cardiac Gland 2. Pyloric - Pyloric Gland 3. Gastric - Gastric or Fundic Gland ## The cells of the gastric gland The cells of the gastric gland are the largest in number and of primary imp...

# Week 9: GI System Drugs – very safe drugs ## 3 Specific Zones of Stomach and Different Glands 1. Cardiac - Cardiac Gland 2. Pyloric - Pyloric Gland 3. Gastric - Gastric or Fundic Gland ## The cells of the gastric gland The cells of the gastric gland are the largest in number and of primary importance when discussing acid control. * **Parietal cells** - secretes HCl acid (H+ stomach, HCO3 →blood) * **Chief cells** - secretes pepsinogen (inactive enzyme)→ pepsin (when pepsinogen encounters acidic environment in the stomach) * **Mucous cells** - secrete mucous ## Secretions from the stomach: * **Hydrochloric acid (HCI)**: Acid that digests & aids to prevent infection * **Bicarbonate**: Base that prevents HCl hyperacidity * **Pepsinogen**: Enzyme that digests dietary proteins as pepsin – eats away protein (when in contact with HCL acid) * **Intrinsic factor**: Glycoprotein that absorbs vit. B12 for RBC production * **Mucous**: Protects the stomach lining from HCl and digestive enzymes (i.e. pepsinogen) * **Prostaglandins**: Anti-inflammatory/protective functions The bicarbonate produced in the parietal cells is actually destined for blood circulation (to balance blood pH) and the hydrogen produced is destined for the stomach. Bicarbonate used to neutralize stomach pH is actually secreted from gastric mucous cells in addition to the protective mucous produced. ## Hydrochloric Acid (HCI) * Hyperacidity (mild/moderate) is the most common gastric problem * Lay terms: indigestion, heartburn, sour stomach, acid stomach * Can be associated with gastroesophageal reflux disease (GERD) * Caused by an overproduction of HCl by parietal cells * HCI is secreted by parietal cells when stimulated by food, caffeine, chocolate, and alcohol, also stimulated by large fatty meals & emotional stress. * Maintains stomach at pH of 1 to 4 * Acidity aids in the proper digestion of food and defenses against microbial infection via the GI tract. ## Acid-Related Diseases * Peptic ulcer disease (PUD) * Gastric or duodenal ulcers that involve digestion of the GI mucosa by the enzyme pepsin * Helicobacter pylori (H. pylori) * Bacterium found in GI tract of people who have peptic ulcer disease (PUD), specifically those with duodenal (90%) and gastric ulcers (70%). * Stress-related mucosal damage * Gl lesions are a common finding in Critical Care Unit patients, especially within the first 24 hours after admission. * Factors include decreased blood flow, mucosal ischemia, hypoperfusion, and reperfusion injury (fyi: when the sudden restoration of blood flow after ischemia through overwhelms fragile tissues, causing damage instead of healing). * Nasogastric tubes predispose patients to GI bleeding. ## Acid-Controlling Drug 1. Antacids 2. H2 antagonists 3. PPIs Mnemonic: “PHA” ## 1. Antacids **MOA** →stimulate gastric mucus cells, increase bicarbonate production/secretion = temporarily neutralizes gastric acidity. * Basic compounds used to raise stomach pH, neutralizing gastric acidity, ↑ stomach PH * Salts of aluminum, magnesium, calcium, or sodium bicarbonate, or all of these * Many antacid preparations also contain the antiflatulent (antigas) drug simethicone. * Many aluminum- and calcium-based formulations also include magnesi Aluminum, Ca – Promote gastric mucosal defensive mechanisms by stimulating the sec **Drug Effects** * **Mucus**: protective barrier against hydrochloric acid → constipation * **Bicarbonate**: helps buffer acidic properties of hydrochloric acia → constipation * **Prostaglandins**: prevent activation of proton pump, which produces HCI acid **Reduction of gastric pain and reflux (i.e., GERD) associated with acid-related disorders** * Raising the gastric pH 1 point (e.g., 1.3 → 2.3) neutralizes 90% of the gastric acid. * Reducing acidity reduces gastric pain as a result of: * Base-mediated inhibition of the protein-digesting ability of pepsin * Increase in the resistance of the stomach lining to irritation * Increase in the tone of the cardiac sphincter (reduces esophageal reflux from the stomach) **Indications** OTC but mainly prescribed for acute relief of symptoms associated with peptic ulcer, gastritis, gastric hyperacidity, and heartburn **Contraindications - pretty safe!** * Stones, hypercalcemia, hypermagnesemia → if taken often or too many * Known allergy * Severe renal failure or electrolyte disturbances * Potential toxic accumulation of electrolytes in the antacids themselves (remember, many antacids contain magnesium, calcium & sodium bicarbonate) * Gl obstruction: * Antacids may stimulate Gl motility when it is specifically undesirable because of the presence of an obstructive process requiring surgical intervention. **Forms Available** Over-the-counter (OTC) formulations available as: capsules and tablets, powders, chewables, suspensions, effervescent tablets or powders **Adverse Effects** Minimal and depend on the compound used **Examples:** * Overuse: metabolic alkalosis * **Aluminum and calcium**: constipation * **Magnesium**: diarrhea * **Calcium**: kidney stones, rebound hyperacidity * **Calcium carbonate**: produces gas and belching; often combined with simethicone **Examples:** 1. Rolaids (Ca,Mg) 2. Maalox (Aluminum hydroxide & Mg) 3. Tums (Ca) 4. Alka-Seltzer (Sodium Bicarbonate) – have aspirin! **Drug Interactions – you are more basic** * Adsorption of other drugs to antacids * Reduces the ability of the other drug to be absorbed into the body * Increased stomach pH * Acidic drugs-better absorbed in acidic environments * Basic (alkaline) drugs - better absorbed in a more alkaline (basic) environment →The absorption of drugs depends on the ph of the environment * Decreases the absorption of acidic drugs * Increased urinary pH * Increased excretion of acidic drugs * Decreased excretion of basic drugs ## 2. H2 Antagonists **MOA** Suppress gastric acid secretion by competitively blocking the H₂ receptor of acid-producing parietal cells. * Therefore, also called "H₂ receptor blockers or H2 receptor antagonists” * Increase in the pH of the stomach * Reduce H ion secretion from the parietal cells * Relieve of many of the symptoms associated with hyperacidity-related conditions **Indications** * Gastroesophageal reflux disease (GERD) * Peptic ulcer disease (PUD) * Erosive esophagitis * Adjunct therapy to control upper GI bleeding **Contraindications** * Allergy * Hepatic or renal dysfunction potentially **Ex.** Famotidine **Adverse Effects** * Overall, very few * CNS adverse effects in elderly patients include confusion and disorientation (<1%) **Drug Interactions** * Smoking has been shown to decrease the effectiveness of H2 blockers. * For optimal results, H2 receptor antagonists are taken 1 hour before antacids (this way we may not need to take Antiacids (“analogy rescue drug/puffer"), H2 antagonist (analogy “long term drug/puffer")) Taking an H2 antagonist before antacids can help reduce the overall need for antacids, as it minimizes the amount of acid the stomach produces in the first place. This is a common strategy to maximize the effect of long-term acid suppression without constantly relying on short-term antacid relief. ## 3. Proton Pump Inhibitors (PPIs) - newest, added on prophylactically for ulcers **MOA** * Irreversibly bind to “Proton (H+) pump" →inhibits movement of H ions out of the acid-secreting parietal cells into the stomach, blocking all gastric acid from parietal cells, so ↑ gastric pH * This results in all gastric acid secretion being temporarily blocked – your parietal cells gets replaced constantly * To return to normal acid secretion, the parietal cell must synthesize new H+/K+ ATPase. * PPIs stop >90% of acid secretion when taken daily **Indications** * Gastroesophageal reflux disease (GERD) * Erosive esophagitis * Short-term treatment of active duodenal and benign gastric ulcers * NSAIDs - as they induced ulcers - NSAIDs causes stomach bleed * Stress ulcer prophylaxis * Treatment of H. pylori-induced infections * Given with the antibiotic clarithromycin (a macrolide) **Contraindications** Allergies **Memory trick:** " _prazole"** * pantoprazole sodium (Pantoloc®) - you can't crush * omeprazole (Losec®) – don't crush * lansoprazole (Prevacid®) **Adverse Effects** * Generally well tolerated. * Osteoporosis and risk of wrist, hip, and spine fractures in long-term users * Possible predisposition to Gl tract infections: Clostridium difficile **Drug Interactions** * Can increase your risk to C.difficile ## Nursing Implications for Acid-Controlling Drugs ### Nursing Implications: Antacids * Other medications should not be taken within 1 to 2 hours after taking an antacid – because maybe we won't even going to take antiacid (unless prescribed) because antacids can impact the absorption of many medications in the stomach. Take them later. * Antacids may cause premature dissolving of enteric-coated medications, resulting in stomach upset. * Administer with at least 240 mL of water to enhance absorption (except for "rapid-dissolve” forms) * Long-term self-medication with antacids may mask symptoms of serious underlying diseases, such as malignancy or bleeding ulcers. Pt may overlook the seriousness of the symptoms they are treating. * If hyperacidity symptoms remain ongoing, the patient should seek medical evaluation * Monitor for adverse effects: * n/v, abdominal pain, diarrhea * With calcium-containing products: constipation, acid rebound * Excess use can result in metabolic alkalosis – if severe renal dysfunction ### Nursing Implications: H2 Antagonist * Assess for impaired renal or liver function. * Use with caution in patients who are confused, disoriented, or in older adult patients. * CNS adverse effects are possible (confusion and disorientation) * Take 1 to 2 hours before antacids → optimal results * For IV doses, follow administration guidelines. ### Nursing Implications: PPIs * Assess for history of liver disease. * May increase serum levels of diazepam and phenytoin; may increase chance for bleeding with warfarin * Teach patient to take prescribed medications exactly as prescribed as it will help cure an ulcer (PUD) caused by H. Pylori → usually a dual therapy of a PPI & clarithromycin * Omeprazole should not be crushed or chewed (enteric-coated) * Most PPI are enteric-coated and should NOT be crushed, chewed, or opened * If PPI is required for a nasogastric, a crushable form is required ## Antidiarrheal Drugs and Laxatives ### Diarrhea Abnormal passage of stools with increased frequency, fluidity, and weight or with increased stool water excretion Consists of 3 + loose or liquid stools per day * **Acute diarrhea** * Sudden onset in a previously healthy person * Lasts from 3 days to 2 weeks * Self-limiting * **Chronic diarrhea** * Lasts for more than 3 to 4 week's, or more * Associated with recurring passage of diarrheal stools, fever, loss of appetite, n/v, weight loss, and chronic weakness ### Causes of Diarrhea | Cause | |---|---| | Acute Diarrhea | Chronic Diarrhea | | Bacteria | Inflammatory bowel disease | | Viruses | Crohn's disease | | Drugs (drug induced) | Ulcerative colitis | | Nutritional factors | Tumor | | C. Diff. | Diabetes | ### Goals of Diarrhea Treatment * Stopping the stool frequency * Alleviating the abdominal cramps * Replenishing fluids and electrolytes – often hypomagnesemia * Preventing weight loss and nutritional deficits from malabsorption ### Antidiarrheals 1. Adsorbents - 2. Probiotics 3. Antimotility (anticholinergics & opiates) Mnemonic "AN-A, PRO" #### 1. Adsorbents **MOA:** * Coat the walls of the gastrointestinal tract, binds to bacteria and gets excreted together * Bind to the causative bacteria or toxin, which is then eliminated through the stool **Examples:** * bismuth subsalicylate (Pepto-Bismol®), - has aspirin → not to kids d/t Reyes Syndrome * activated charcoal * antilipemic drugs (cholestyramine) #### 2.Probiotics * Probiotics are products obtained from bacterial cultures (mainly Lactobacillus organisms) * Also known as “intestinal flora modifiers/ bacterial replacement drugs” * Normal bacterial flora is often destroyed by antibiotics → leads to diarrhea * Bacterial cultures of Lactobacillus organisms work by: * Supplying missing bacteria to the Gl tract * Suppressing the growth of diarrhea-causing bacteria * we introduce good bacteria to px diarrhea when abx has disrupted flora and was wiped clean #### 3.Antimotility (anticholinergics & opiates) * Two subclasses of drugs which slow motility through the GI: ##### 1. Antimotility drugs: anticholinergics * Slow peristalsis by reducing the rhythmic contractions and smooth muscle tone of the GI tract * Have a drying effect on liquid stools * Reduce gastric secretions ##### 2. Antimotility drugs: opiates - focus on this class mostly * Decrease bowel motility and reduce pain by relief of rectal spasms * Increase transit time (food stays in the intestines longer) through the bowel, allowing more time for water and electrolytes to be absorbed * Examples: loperamide (Imodium) ** opiates in this class don't work the same as opioids **Indications** * Adsorbents: Milder cases * Probiotics: Antibiotic-induced diarrhea * Antimotility (anticholinergics and opiates): More severe cases **Contraindications** * Allergy * Diarrhea caused by bacteria or parasite ** ex C. diff = lets it run it course * Acute Gl conditions such as intestinal obstruction or colitis (relative contraindications) **Adverse Effects** * Adsorbents * Increased bleeding time/bruising when taken with anticoagulants, constipation/dark stools * Antimotility (Anticholinergics) * Hypotension, bradycardia, blurred vision & dry skin (drying effects), urinary retention * CNS: headache, dizziness, confusion, anxiety * Antimotility (Opiates) * Drowsiness, dizziness, lethargy. N/V, constipation, respiratory depression, hypotension, urinary retention * none for Probiotics! **Antidiarrheals** **Drug Examples** * Adsorbents: Bismuth subsalicylate (Pepto-Bismol) * Probiotics: Lactobacillus * Antimotility (Opiates) no anticholinergic: Loperamide hydrochloride (Imodium) **Interactions** * Adsorbents -> decrease the absorption of many drugs, including digoxin and hypoglycemic drugs. * Adsorbents -> increased bleeding time and bruising when given with anticoagulants (warfarin). **Nursing Implications: Antidiarrheals** **DON'T give bismuth subsalicylate (Pepto-Bismol-has aspirin) to children or teenagers with chicken pox or influenza because of the risk of Reye syndrome.** * Use adsorbents carefully in older adult patients and those with decreased bleeding time, clotting disorders, recent bowel surgery, or confusion ### Constipation * Abnormally infrequent and difficult passage of feces through the lower Gl tract * A symptom, not a disease * Disorder of movement through the colon or rectum * Can be caused by a variety of diseases or drugs * Treatment can include surgical and nonsurgical such as: * Laxatives * Dietary (fibre) * Behavioural (increased physical activity) * Pharmacological (Laxatives) ### Laxatives 1. Bulk Forming 2. Emollient 3. Hyperosmotic 4. Stimulants Mnemonic: “HY, EMO BU-S" #### 1. Bulk-forming * **MOA:** * High fiber - pseudo fiber; absorb water into the intestine → distends bowel with added 'bulk' to trigger bowel activity * **Examples:** psyllium (Metamucil®) → don't give it thru tubes! #### 2.Emollient * **MOA:** * Stool softeners: Promote more water and fat in the stools. - docusate sodium (Colace®) * Lubricants: Lubricate the fecal material and intestinal walls. - mineral oil #### 3.Hyperosmotic * **MOA:** * Increase fecal water content resulting in bowel distention & increased peristalsis * **Examples:** * Polyethylene glycol (Lax-A-Day) * Lactulose (also used to reduce elevated serum ammonia levels)- causes more cramps #### 4.Stimulants * **MOA:** * Increase peristalsis via intestinal nerve stimulation, can make up more dependent on the drug * **Examples:** * senna (Senokot®) * bisacodyl (Dulcolax®) ### Indications: | Laxative Group | Use | |---|---| | 1. Bulk forming | * Acute and chronic constipation * IBS * Diverticulosis * Psyllium (Metamucil) * Acute and chronic constipation, * Docusate sodium (Colace) | | 2. Emollient | * Chronic constipation, * Diagnostic and surgical procedures * Polyethylene glycol (Lax-A-Day)/lactulose | | 3. Hyperosmot ic | * Acute constipation, * Diagnostic * Surgical procedures | | 4. Stimulant | * Senna (Senokot)/bisacodyl (Dulcolax) | ### Contraindications * Intestinal obstruction * Abdominal pain * N&V * Undiagnosed abdominal pain * Acute surgical abdomen Basically, acute GI ### Adverse Effects 1.Bulk-forming: Impaction; gas formation; allergic reaction 2.Emollient: Skin rashes; decreased absorption of vitamin A; lipid pneumonia 3.Hyperosmotic: Abdominal bloating; rectal irritation 4.Stimulant: * Nutrient malabsorption * Gastric irritation * Rectal irritation * Dependence * **All laxatives can cause electrolyte disturbances!** ### Nursing Implications * Assess fluid and electrolytes before initiating therapy. * Long-term use of laxatives often results in decreased bowel tone and may lead to dependency. * All laxative tablets should be swallowed whole, not crushed or chewed, especially if enteric-coated * Patients should take bulk forming laxatives with 240 mL of water (1 cup). Laxative tabs with 180-240 ml of water. * Give bisacodyl with water only on an empty stomach because of interactions with milk, antacids, and juices. * Inform patients to contact their prescribers if they experience severe abdominal pain, muscle weakness, cramps, or dizziness, which may indicate possible fluid or electrolyte loss. ### Nausea & Vomiting (emesis) * Types of Nausea and Vomiting * General * Postoperative * Chemotherapy induced ### Antiemetics and Antinausea Drugs – purpose is to relieve n/v 1. Antihistamines (histamine 1 [H1] receptor blockercl 2. Serotonin blockers 3. Prokinetic drugs **Focus is on this two antiemetics: Antihistamines & Serotonin blockers!** | Antiemetic Class | Antiemetic Example | Mechanism of Action | |---|---|---| | Antihistamines (histamine 1 [H1] receptor blockers) | dimenhydrinate (Gravol) diphenhydramine (Benadryl®) | Inhibits vestibular stimulation → prevents N&V **Most commonly used & safest** | | Serotonin blockers | ondansetron (Zofran®) | Blocks serotonin receptors in the Gl tract and vomiting centre → prevents N&V | | Prokinetic | Metoclopramide (Maxeran®) | Stimulates peristalsis in the GI → emptying stomach contents into duodenum → prevents N&V | #### 1.Antihistamine drugs (H₁ receptor blockers) **MOA:** * Inhibit acetylcholine by binding to H₁ receptors * Prevent cholinergic stimulation in vestibular and reticular areas (brainstem), thus preventing n/v * Also used for motion sickness, allergy symptoms, sedation **Examples:** * dimenhydrinate (Gravol®) * diphenhydramine (Benadryl®) **don't confuse them!** #### 2.Serotonin blockers **MOA:** * Block serotonin receptors in the Gl tract and vomiting centre * Used for n/v in patients receiving chemotherapy and for postoperative n/v * Example: ondansetron (Zofran®) #### 3.Prokinetic drugs **MOA:** * Block dopamine receptors in the medulla oblongata of the brain (contains receptors that become stimulated to induce vomiting) * Causes the medulla oblongata to be desensitized to impulses it receives from the Gl tract * Also, stimulates peristalsis in the Gl tract, enhancing emptying of stomach contents * Also used for gastroesophageal reflux disease (GERD) and delayed gastric emptying * Example: metoclopramide (Metonia®) **Adverse Effects** * Vary according to drug used * Most cause drowsiness and hypotension * Ondansetron cause h/a * Some given 30 to 60 minutes BEFORE chemotherapy **Nursing Implications** * Assess complete nausea and vomiting history, including precipitating factors. * Assess current medications. * Assess for contraindications and potential drug interactions. * Many of these drugs cause severe drowsiness; warn patients about driving or performing any hazardous tasks. * Taking antiemetics with alcohol may cause severe CNS depression. * Antiemetics should be given 30 to 60 minutes before a chemotherapy drug is given **Nutritional Supplements** * Adequate nutrition is required for cell growth, muscle contraction, wound repair, immune integrity, nutrition (wt gain) etc, so likely your patient will have the opposite. * Main concern → malnutrition * Dietary products used to provide nutritional support * Can be given in a variety of ways * Vary in amounts and complexity of macros, micros, Lytes and osmolality content ## Types: 1. **Enteral Nutrition** - works in GI 2. **Parenteral Nutrition** - everything but Gl, into circul ### 1. Enteral Nutrition * Provision of food or nutrients through the gastrointestinal tract * By oral route or feeding tube, oral is the most common and least invasive route. * Feeding tubes through various routes can be used for enteral nutrition (e.g., NG, NJ, G-tul **Feeding tube indications** * Abnormal esophageal or stomach peristalsis * Altered anatomy secondary to surgery * Depressed consciousness * Impaired digestive capacity * Severe malnutrition (eating disorder - anorexia nervosa **Enteral Formulation Groups x5** * Provide basic building blocks for anabolism * Supply complete dietary needs through the Gl tract by oral rou **Interactions** * Various nutrients can interact with drugs * Enteral nutrition can delay absorption of some medications (e.g., penicillin). * Enteral nutrition may decrease the effects of some medications **Adverse Effects** * Gl intolerance: diarrhea * Dumping syndrome * Movement of food (sugars) too rapidly from stomach into duodenum * Symptoms can include n/v, abdo pain, diarrhea, weakness, hypoglycemia * Aspiration pneumonia ### 2.Parenteral Nutrition (TPN) * Totally digested nutrients are given IV, directly into the circulatory system → via a central line * The entire Gl system is bypassed, eliminating the need for ADME (pharmacokinetics) * For patients who are unable to tolerate or maintain adequate enteral nutrition * Gives hyperalimentation to pt unable to meet those needs * Formulations vary according to individual patient nutritional needs (often calculated by a registered dietician based on daily bloodwork) * you check routinely blood glucose for the risk of hyperglycemia and hypoglcemia * TPN is double-check (orders and bags) before given to the patient * Always requires a filter ## Parenteral Nutrition (Total Parenteral Nutrition – TPN) **Each TPN bag contains:** * **Bag #1 (yellow):** * Amino acids, carbohydrates, trace elements, electrolytes, vitamins, fluids (dextrose 10-50%) * **Bag #2 (white):** * Lipids (10-30%) * Supplemental insulin (subcutaneous) may be ordered to be given while patient is being administered TPN due to the high levels of dextrose **Via Central Line** * Delivered through large vein * Delivers total dietary nutrients to patients who require nutritional supplementation * Patients with large nutritional requirements (metabolic stress or hypermetabolism - states where the pt requires more nutrients and energy) * Patients who need nutritional support for more than 7 to 10 days * Patients who are unable to tolerate large fluid loads **Disadvantages are the risks associated with central line insertion, use, and maintenance** * Higher risk for infection, catheter-induced trauma, metabolic alterations **Adverse Effects** * Most common are those surrounding the use of the central line for the delivery of TPN * Infection * Catheter-induced trauma * Greater chance for hyperglycemia because of the larger and more concentrated volumes given * Fluid overload * Phlebitis – if given via peripheral vein **Nursing Implications: Enteral** * Registered Dietician should be consulted * Assess baseline laboratory studies, such as: * total protein, * albumin, * blood urea nitrogen, * RBC count, * WBC count, * cholesterol * Assess nutritional status. * Assess for allergies to components of enteral nutritional supplements (e.g., whey, egg whites). * Assess for lactose intolerance. * If administering enteral nutrition by tube feedings, follow facility policy for ensuring proper tube placement (i.e., gastric bubble test, residual test, and X-ray) and for checking residual volumes before administering a feeding. * If the volume aspirated is more than the volume delivered over previous 2 hours: * Return aspirated content back into tube * Hold the feeding * Contact the HCP * Keep patient's head elevated to prevent aspiration pneumonia * Follow procedures for flushing tubing to prevent clogging the feeding tube with formula. * Carefully monitor how the patient is tolerating enteral feedings. * fluid balance (Ins & Outs) * fluid overload (severe adverse effect of feedings) * Keep in mind that most enteral feedings are started slowly, and the rate is increased gradually to ensure tolerance * Monitor for signs of gastric intolerance: * Cramping * Diarrhea * Abdominal bloating * Flatulence **Nursing Implications: TPN** * Monitor blood glucose levels with a glucometer * Watch for and monitor for: * hyperglycemia: h/a, dehydration, weakness * hypoglycemia: cold, clammy skin; dizziness; tachycardia; tingling of the extremities * Diligent care and maintenance of TPN IV lines, including tubing and dressing changes. * To ensure patient safety, TPN infusion should be assessed every 60 minutes * Monitor patient's temperature; report any increase immediately. * While on TPN, the pancreas provides increased amounts of insulin to cover the increased glucose levels, if TPN is discontinued abruptly, rebound hypoglycemia may occur until the pancreas has time to adjust to changing glucose levels. * If TPN must be discontinued abruptly, then infuse 5 to 10% glucose to prevent rebound hypoglycemia, according to facility policy. Important to not delay administration of 10% glucose solution to prevent rebound hypoglycemia. * Watch for and monitor for fluid overload while patient is on TPN. * Weak pulse * Hypertension * Tachycardia * Confusion * Decreased urine output * Pitting edema * Pulmonary edema * Monitor daily weights and intake and output volumes. * Assess infusion hourly ## Weekly Summary * The stomach secretes many substances including HCI acid * Stomach acidity can be influenced by several drugs * Diarrhea is leading cause of mortality in the world * Multiple indications for use of antiemetics most of which cause drowsiness, some cause hypotension * Treatment with enteral feeding may result in hyperglycemia, dumping syndrome, aspiration ## Table 7.6a Comparing Medications Used to Treat Diarrhea [21][22][23] | Class | Prototype/Generic | Administration Considerations | Therapeutic Effects | Adverse/Side Effects | |---|---|---|---|---| | Adsorbents | bismuth subsalicylate (Pepto Bismol) | Avoid if taking other salicylates. Do not use in children or teenagers recovering from chickenpox or flu-like symptoms as may cause Reye's syndrome. Do not use if the client has an ulcer, bleeding problem, or bloody or black stool. | Decreased diarrhea symptoms | May cause black or darkened tongue. Contact provider if symptoms worsen, a fever or ringing in the ears occurs, or if diarrhea lasts longer than 48 hours. | | Anticholinergic | hyoscyamine | Contraindicated in glaucoma, myasthenia gravis, or paralytic ileus. Contraindicated in children younger than 2 and with several other medications; read drug label information before administering. | Decreased diarrhea symptoms | May cause CNS and other adverse effects associated with anticholinergic medication. | | Opiate-like medication | loperamide (Imodium) | | Decreased diarrhea symptoms | Black Box Warning: May cause abnormal heart rhythm. | ## Table 7.6b Categories of Laxatives Used to Treat Constipation | Category | Prototypes | Mechanism of Action | |---|---|---| | Fiber supplements | psyllium (Metamucil) | Bulk-forming to facilitate passage of stool through the rectum | | Stool softeners | Docusate (Colace) | Facilitates movement of water and fats into stool | | Osmotic agents | Milk of Magnesia; polyethylene glycol (PEG) 3350 (Miralax) | Causes water to be retained with the stool, increasing the number of bowel movements and softening the stool so it is easier to pass | | Lubricants | mineral oil enema (Fleet) | Coats the stool to help seal in water | ## Table 7.6c Comparing Laxatives | Prototype/Generic | Administration Considerations | Therapeuti c Effects | Adverse/Side Effects | |---|---|---|---| | psyllium (Metamucil) | Put one dose into an empty glass and mix with at least 8 ounces of water or other fluid. Taking this product without enough liquid may cause choking. Stir briskly and drink promptly. If mixture thickens, add more liquid and stir. Usually produces a bowel movement within 12 to 72 hours. Administer at least 2 hours before or 2 hours after other medications as it can affect absorption. Start with 1 dose per day; may gradually increase to 3 doses per day as necessary. | Improves regularity of bowel movements. | May cause bloating and cramping. | | docusate | Usually produces bowel movement in 12 to 72 hours. | Softens stool and improves regularity of bowel movements. | May cause abdominal cramping. | | polyethylene glycol 3350 (Miralax) | Usually produces a bowel movement in 1-3 days. The bottle top is a measuring cap marked to contain 17 grams of powder when filled to the indicated line. For adults and children 17 years of age and older: * fill to top of clear section in cap, which is marked to indicate the correct dose (17 g) * stir and dissolve in any 4 to 8 ounces of beverage (cold, hot or room temperature) and then drink * use once a day * use no more than 7 days | Softens stool and improves regularity of bowel movements. | May cause loose, watery stools. | | Mineral oil enema | Read drug labels for children as some brands can be used in children aged 2 or older, whereas others are not intended for children. Generally produces bowel movement in 2 to 15 minutes. | Bowel movement within 15 minutes. | Stomach cramps, bloating, upset stomach, or diarrhea. | | bisacodyl | Oral dosage or rectal suppositories are available. To administer a rectal suppository: Position client on left side with the right knee up towards the chest. In the presence of anal fissures or hemorrhoids, suppositories should be coated at the tip with petroleum jelly. Remove foil and insert suppository well into rectum touching the bowel wall. Instruct client to retain suppository for about 15 to 20 minutes. A bowel movement is generally produced in 15 minutes to one hour. For children, read drug labels for dosage. | Bowel movement within one hour. | Stomach cramps, dizziness, or rectal burning. |