Acid Reducers, Antidiarrheals, Laxatives - NUR 2403 - Class Slides PDF

Acid Reducers, Antidiarrheals, Laxatives NUR 2403 – Week 4 Housekeeping Reminder about class observation Questions from last week Case study and discussion questions GERD Quiz at the end of class (1345h) What do the cells in the stomach secrete? Hydrochloric acid (HCl) Bicarbonate P...

Acid Reducers, Antidiarrheals, Laxatives NUR 2403 – Week 4 Housekeeping Reminder about class observation Questions from last week Case study and discussion questions GERD Quiz at the end of class (1345h) What do the cells in the stomach secrete? Hydrochloric acid (HCl) Bicarbonate Pepsinogen Intrinsic factor Mucus Prostaglandins Anatomy Refresher Cardiac Pyloric Gastric The cells of the gastric gland are the largest in number Primary importance when discussing acid control Cells of the Gastric Gland Parietal Produce and secrete hydrochloric acid Primary site of action most drugs used to treat acid-related disorders Chief Secrete pepsinogen, a proenzyme Pepsinogen becomes pepsin when activated by exposure to acid Pepsin breaks down proteins (proteolytic) Mucous Provide a protective mucus coat Protect against self-digestion by hydrochloric acid and digestive enzymes Hydrochloric Acid Secreted by parietal cells when stimulated by food, caffeine, chocolate, and alcohol Maintains stomach at pH of 1 to 4 Acidity aids in the proper digestion of food Defends against microbial infection via the GI tract Secretion also stimulated by: Large fatty meals Emotional stress Parietal Cell Stimulation and Secretion Acid-Related Diseases Peptic ulcer disease Gastric or duodenal ulcers that involve digestion of the GI mucosa by the enzyme pepsin Helicobacter pylori (H. pylori) Up to 90% of ulcers Triple therapy 7-14-day course of a PPI and clarithromycin and either amoxicillin or metronidazole Quadruple therapy - PPI, bismuth subsalicylate, tetracycline and metronidazole. Acid-Related Diseases Stress-related mucosal damage Common in ICU, especially within the first 24 hours after admission Factors include decreased blood flow, mucosal ischemia, hypoperfusion, and reperfusion injury Nasogastric tubes and ventilators predispose patients to GI bleeding A histamine receptor–blocking drug or a PPI are given for prevention Types of Acid-Controlling Drugs Antacids H2 antagonists Proton Pump Inhibitors (PPIs) Antacids Basic compounds used to neutralize stomach acid Salts of aluminum, magnesium, calcium, or sodium bicarbonate Some also contain the antiflatulent drug simethicone Many aluminum- and calcium-based formulations also include magnesium Antacids: Mechanism of Action Neutralizing acidity Do not prevent the overproduction of acid Promote gastric mucosal defensive mechanisms Stimulate secretion of: Mucus: protective barrier against hydrochloric acid Bicarbonate: helps buffer acidic properties of hydrochloric acid Prostaglandins: prevent activation of proton pump Antacids: Drug Effects Reduction of pain and reflux associated with acid-related disorders Raising the gastric pH 1 point (1.3 to 2.3) neutralizes 90% of the gastric acid. Acute relief of symptoms associated with peptic ulcer, gastritis, gastric hyperacidity, and heartburn Antacids: Types Used alone or in combination Aluminum hydroxide (hypercalcemia, constipation) Magnesium hydroxide (diarrhea) Calcium (kidney stones) Sodium bicarbonate (alkalosis Simethicone OTC formulations available as: Capsules and tablets Powders Chewable tablets Suspensions Effervescent granules and tablets Antacids: Aluminum Salts Have constipating effects Often used with magnesium to counteract constipation Often recommended for patients with renal disease (easily excreted) Examples Combination products (aluminum and magnesium): Antacid Plus®, Diovol®, Gelusil®, Maalox® Antacids: Magnesium Salts Commonly cause diarrhea; usually used with other drugs to counteract this effect Dangerous when used with renal failure; the failing kidney cannot excrete extra magnesium, resulting in accumulation ‘milk of magnesia’ Magnesium hydroxide and mineral oil (Magnolox®) Antacids: Calcium Salts Many forms but carbonate is most common May cause constipation, kidney stones Also not recommended for patients with renal disease Long duration of acid action—may cause hyperacidity rebound Often advertised as an extra source of dietary calcium Example: calcium carbonate and simethicone (Maalox, Rolaids®) Antacids: Sodium Bicarbonate Highly soluble Buffers the acidic properties of hydrochloric acid Quick onset but short duration **May cause metabolic alkalosis Sodium content may cause problems in patients with HF, HTN Antacids: Contraindications Severe renal failure or electrolyte disturbances: potential toxic accumulation of electrolytes in the antacids themselves Gastrointestinal obstruction: Antacids may stimulate gastrointestinal motility Interactions with many other meds (2 hour rule) Effecting absorption H2 Receptor Antagonists Reduce acid secretion All available OTC in lower-dosage forms Most popular drugs for treatment of acid-related disorders cimetidine ranitidine hydrochloride (Zantac®) famotidine (Pepcid®) H2 Antagonists: Mechanism of Action Competitively block the H2 receptor of acid-producing parietal cells Reduce hydrogen ion secretion from the parietal cells Suppressed acid secretion in the stomach Increase pH of the stomach Relieve of many of the symptoms associated with Gastroesophageal reflux disease (GERD) Peptic ulcer disease Erosive esophagitis Adjunct therapy to control upper gastrointestinal bleeding Zollinger-Ellison syndrome H2 Antagonists: Adverse Effects Overall, very few adverse effects Central nervous system adverse effects in elderly patients include confusion and disorientation Cimetidine - may cause erectile dysfunction and gynecomastia Thrombocytopenia has been reported with ranitidine and famotidine H2 Antagonists: 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. All H2 antagonists may inhibit the absorption of drugs that require an acidic gastrointestinal environment for absorption Cimetidine has been mostly replaced by ranitidine and famotidine Interactions with many other meds primarily r/t gastric pH Proton Pump Inhibitors The parietal cells release positive hydrogen ions (protons) during hydrochloric acid production. This process is called the proton pump. H2 blockers do not stop the action of this pump. Proton Pump Inhibitors: MOA Irreversibly bind to H+/K+ adenosine triphosphatase (ATPase) enzyme This bond prevents the movement of hydrogen ions from the parietal cell into the stomach. Results in achlorhydria—all gastric acid secretion is temporarily blocked. To return to normal acid secretion, the parietal cell must synthesize new H+/K+ ATPase. Proton Pump Inhibitors lansoprazole (Prevacid®) omeprazole (Losec®) rabeprazole sodium (Pariet®) pantoprazole sodium (Pantoloc®) esomeprazole trihydrate (Nexium®) dexlansoprazole (Dexilant®) Proton Pump Inhibitors: Indications Gastroesophageal reflux disease Erosive esophagitis Short-term treatment of active duodenal and benign gastric ulcers Zollinger-Ellison syndrome Nonsteroidal anti-inflammatory drug (NSAID)–induced ulcers Stress ulcer prophylaxis Treatment of H. pylori–induced infections Given with an antibiotic Proton Pump Inhibitors: Adverse Effects Protein pump inhibitors (PPIs) are generally well tolerated short term Possible predisposition to gastrointestinal tract infection C difficile Osteoporosis and risk of wrist, hip, and spine fractures in long-term users Pneumonia Depletion of magnesium Proton Pump Inhibitors: Interactions Increase serum levels of diazepam and phenytoin Warfarin: increased chance of bleeding Absorption of ketoconazole, ampicillin, iron salts, and digoxin Sucralfate: may delay the absorption of PPIs Food may decrease absorption of the PPIs. Take PPIs on an empty stomach Sucralfate Mucosal protectant for stress ulcers, peptic ulcer disease Attracted to and binds to the base of ulcers and erosions, forming a protective barrier over these areas May cause constipation, nausea, and dry mouth May impair absorption of other drugs. Give other drugs at least 2 hours before sucralfate. Binds with phosphate; may be used in chronic renal failure to reduce phosphate levels Simethicone Antiflatulent drug Used to reduce the discomforts of gastric or intestinal gas Alters elasticity of mucus-coated gas bubbles, breaking them into smaller ones Result is decreased gas pain and increased expulsion via mouth or rectum. Nursing Implications: Antacids Be sure that chewable tablets are chewed thoroughly and that liquid forms are shaken well before giving. Administer with at least 240 mL of water to enhance absorption Long-term self-medication with antacids may mask symptoms of serious underlying diseases, malignancy or bleeding ulcers. Nursing Implications: H2 Antagonists Assess for allergies and impaired renal or liver function. Use with caution in patients who are confused, disoriented, or in older adult patients. Take 1 to 2 hours before antacids. For intravenous doses, follow administration guidelines. Nursing Implications: PPIs Assess for allergies and history of liver disease. Not all are available for parenteral administration. May increase serum levels of diazepam and phenytoin; may increase chance for bleeding with warfarin The granules of pantoprazole capsules may be given via nasogastric tubes after dilution Capsules may be opened and mixed with apple juice, but delayed-release granules are not to be crushed or chewed. Question A patient who has chronic renal failure wants to self-treat with an antacid for occasional heartburn. Which medication is the best choice for this patient? A. A magnesium-containing antacid B. A calcium-containing antacid C. An aluminum-containing antacid D. Because of renal problems, the patient should not take antacids for this problem. Question When working with an older adult patient who has been admitted for a possible gastrointestinal bleed, the nurse identifies which drug as having the potential to cause confusion and disorientation? A. An antacid B. A protein pump inhibitor C. An H2 antagonist D. A mucosal protectant Question When providing education regarding the use of protein pump inhibitors, which statement will the nurse include? A. “Take the medication along with the first meal of the day.” B. “Take the medication on an empty stomach, 30 to 60 minutes before eating.” C. “Take the medication when you have symptoms of heartburn.” D. “Take the medication at bedtime with a snack.” Diarrhea 2nd leading cause of death in children 3 or more loose or watery stools per day IBS, Diabetes, IDS, Crohn's, colitis, infection Cause impacts treatment choice Goals of Diarrhea Treatment Stopping the stool frequency Alleviating the abdominal cramps Replenishing fluids and electrolytes Preventing weight loss and nutritional deficits from malabsorption Antidiarrheals Adsorbents Antimotility drugs (anticholinergics and opiates) Probiotics (intestinal flora modifiers and bacterial replacement drugs) Antidiarrheals: Indications Adsorbents: milder cases Anticholinergics and opiates: more severe cases Probiotics: antibiotic-induced diarrhea Mechanism of Action Adsorbents Coat the walls of the gastrointestinal tract Bind to the causative bacteria or toxin, which is then eliminated through the stool Examples: bismuth subsalicylate (Pepto-Bismol®), activated charcoal, and antilipemic drugs colestipol and cholestyramine Antimotility drugs: anticholinergics Decrease intestinal muscle tone and peristalsis of gastrointestinal tract Result: slows the movement of fecal matter through the gastrointestinal tract Example: hyoscyamine, atropine Mechanism of Action Antimotility drugs: opiates Decrease bowel motility and reduce pain by relief of rectal spasms Decrease transit time through the bowel, allowing more time for water and electrolytes to be absorbed Examples: codeine phosphate, loperamide hydrochloride, diphenoxylate Probiotics Also known as intestinal flora modifiers and bacterial replacement drugs Bacterial cultures of Lactobacillus organisms work by Supplying missing bacteria to the gastrointestinal tract Suppressing the growth of diarrhea-causing bacteria Example: Lactobacillus acidophilus Antidiarrheals: Adverse Effects Adsorbents Anticholinergics Increased bleeding time Urinary retention, sexual dysfunction Constipation, dark stools Headache, dizziness, confusion, Confusion anxiety, drowsiness Tinnitus Dry skin, flushing Metallic taste Blurred vision Blue gums Hypotension, bradycardia Opiates Drowsiness, dizziness, lethargy Respiratory depression Hypotension Antidiarrheals: Interactions Adsorbents decrease the absorption of many drugs, including digoxin, quinidine sulphate, and hypoglycemic drugs. Adsorbents cause increased bleeding time and bruising when given with anticoagulants (warfarin). Toxic effects of methotrexate are more likely when given with adsorbents. Antidiarrheals: Nursing Implications Obtain a thorough history of bowel patterns, general state of health, and recent history of illness or dietary changes. Do not give bismuth subsalicylate to children or teenagers with chicken pox or influenza because of the risk of Reye’s syndrome. Use adsorbents carefully in older adult patients and those with decreased bleeding time, clotting disorders, recent bowel surgery, or confusion. Avoid in patients with a history of narrow-angle glaucoma, gastrointestinal obstruction, myasthenia gravis, paralytic ileus, or toxic megacolon. Constipation Abnormally infrequent and difficult passage of feces Symptom, not a disease Usual time from ingestion to defecation 24-36 hours Use of Bristol stool chart Laxatives Bulk forming Emollient (stool softeners, lubricant laxatives) Hyperosmotic Saline Stimulant Mechanism of Action Bulk forming Emollients High fiber -Absorb water to ↑ bulk Stool softeners and lubricants Distend bowel to initiate reflex Promote more water and fat in bowel activity the stools psyllium (Metamucil®) Lubricate the fecal material and Methylcellulose intestinal walls Stimulants Stool softeners: docusate salts Increase peristalsis via intestinal (Colace®) nerve stimulation Lubricants: mineral oil senna (Senokot®) bisacodyl (Dulcolax®) Mechanism of Action Hyperosmotic Saline Increase fecal water content Increases osmotic pressure within Results in bowel distention, the intestinal tract, causing more increased peristalsis, and water to enter the intestines evacuation Results in bowel distention, Polyethylene glycol increased peristalsis, and evacuation Sorbitol, glycerin Magnesium hydroxide (Milk of Lactulose (also used to reduce Magnesia®) elevated serum ammonia Magnesium citrate levels) Laxatives: Indications Laxative group/use Bulk forming: Acute and chronic constipation, irritable bowel syndrome, diverticulosis Emollient: Acute and chronic constipation, fecal impaction, facilitation of bowel movements in anorectal conditions Hyperosmotic: Chronic constipation, diagnostic and surgical procedures Saline: Constipation, diagnostic and surgical procedures Stimulant: Acute constipation, diagnostic and surgical procedures Laxatives: Adverse Effects Bulk forming Emollient Impaction Skin rashes Fluid overload Decreased absorption of Electrolyte imbalances vitamins Gas formation Electrolyte imbalances Esophageal blockage Lipid pneumonia Allergic reaction Laxatives: Adverse Effects Hyperosmotic Stimulant Abdominal bloating Nutrient malabsorption Electrolyte imbalances Skin rashes Rectal irritation Gastric irritation Saline Electrolyte imbalances Magnesium toxicity Discoloured urine Cramping Rectal irritation Electrolyte imbalances All can disrupt electrolytes Cramping, diarrhea Increased thirst Laxatives: Nursing Implications Assess fluid and electrolytes before initiating therapy. Inform patients not to take a laxative if they are experiencing nausea, vomiting, or abdominal pain. A healthy, high-fibre diet and increased fluid intake should be encouraged as an alternative to laxative use. 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. Laxatives: Nursing Implications Patients should take bulk-forming laxatives as directed by the manufacturer with at least 240 mL (8 oz) of water. Give bisacodyl with water 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. Question The antidiarrheal drug Lomotil® contains both diphenoxylate, a synthetic opiate agonist, and atropine, an anticholinergic. What is the purpose of the atropine in this combination? A. To enhance the effects of the diphenoxylate B. To discourage recreational use of the opiate diphenoxylate C. To counteract the adverse effects of the diphenoxylate D. To act as an adsorbent for bacteria in the bowel Question A patient is taking lactulose four times a day but does not have a history of constipation. In fact, the patient has had bowel movements every day. What is the probable reason for the lactulose? A. Cleansing the bowel before a procedure B. Removal of helminths C. Reduction of high ammonia levels associated with liver failure D. Daily maintenance to prevent constipation Question A 48-year-old patient who has been admitted with abdominal pain has not had a bowel movement for 4 days. The patient’s abdomen is distended and slightly tender. Which laxative would be appropriate for this patient? A. Milk of Magnesia B. A bulk-forming laxative C. Mineral oil D. No laxative should be given at this time. Case Study A 56-year-old male patient, Mr. Johnson, is admitted to the hospital with complaints of severe heartburn and regurgitation, along with epigastric pain. He has a history of GERD and is currently prescribed an H2 antagonist (ranitidine) and an occasional PPI (omeprazole) for symptom management. Refer to Moodle for discussion questions Wrap-up Questions? Quiz Week 5: GI meds continued (antiemetics, nutrition supplementation, etc.)