GI Medications Mucosal Protective Agents.pdf

GI Medications Mucosal Protective Agents Debra Forzese, Pharm. D. Mucosal Protective Agents Sucralfate Sucralfate (Carafate) Complex of sucrose and aluminum hydroxide Beneficial in treatment of GI irritations including reflux esophagitis and peptic ulceration Used in combination with 2 antibiotics i...

GI Medications Mucosal Protective Agents Debra Forzese, Pharm. D. Mucosal Protective Agents Sucralfate Sucralfate (Carafate) Complex of sucrose and aluminum hydroxide Beneficial in treatment of GI irritations including reflux esophagitis and peptic ulceration Used in combination with 2 antibiotics in healing of duodenal ulcers and eradication of H pylori Initial treatment of GERD in pregnancy since poorly absorbed Low systemic effects and toxicity because it is only slightly absorbed from GI tract Sucralfate Activated by acid, so sucralfate should be taken on empty stomach 1 hour before meals Avoid use of antacids within 30 minutes of sucralfate dose Avoid in patients with renal failure who are at risk for aluminum overload Viscous layer formed by sucralfate can inhibit absorption of other drugs such as digoxin, phenytoin, ketoconazole, fluoroquinolones Sucralfate Indication o Short term treatment (< 8 weeks) of active duodenal ulcers o Maintenance therapy for duodenal ulcers (tablets) o Off label for GERD in pregnancy Sucralfate Dosing o Adult o Pediatric o Renal Impairment – no dose adjustment o Hepatic Impairment – no dose adjustment Sucralfate Mechanism of Action o Forms a cytoprotective gel covering gastric mucosa protecting against peptic acid, pepsin, and bile salts for up to 6 hours after dose (acidic environment) oPromotes tissue growth and repair Sucralfate Pharmacokinetic/Pharmacodynamic Factors o Onset of action 1-2 hours o Minimal absorption from GI tract o Works locally at sites of ulcer (no systemic activity) o No hepatic metabolism o Excreted primarily in the urine Sucralfate Adverse Effects o Constipation is most common side effect Warnings o Hyperglycemia reported with sucralfate suspension in patients with diabetes o Acts locally at ulcer site, does not alter recurrence/severity of duodenal ulceration o Use cautiously with advanced kidney impairment – potential accumulation of aluminum Sucralfate Use tablets with caution in patients with impaired swallowing, aspiration reported Formulations - oral suspension and tablets Administration usually two to four times daily Sucralfate Drug Interactions o Digoxin – sucralfate reduces blood level of digoxin o Furosemide – sucralfate reduces furosemide level o Ketoconazole – sucralfate reduces ketoconazole concentration o Multivitamins with minerals – may increase concentration of sucralfate o Quinidine –sucralfate decreases level of quinidine o Quinolones – sucralfate can reduce serum concentration of quinolones Sucralfate Pregnancy – acceptable for use in pregnancy, minimal absorption Breastfeeding – use considered acceptable, manufacturer recommends use with caution Monitoring o Blood glucose levels (diabetics receiving oral suspension) Mucosal Protective Agents – Prostaglandin Analogs Misoprostol (Cytotec) Indications oReduced risk of NSAID induced gastric ulcers oTermination of pregnancy Misoprostol Dosing Adult Pediatric Renal impairment – no dose adjustment needed Hepatic impairment – no dose adjustment needed Misoprostol Mechanism of action Reduce intracellular cAMP and gastric acid secretion Provide cytoprotective effects by stimulating mucin and bicarbonate and increased mucosal blood flow Misoprostol Pharmacokinetic/Pharmacodynamic Factors Rapidly absorbed Hepatic metabolism to active form (misoprostol acid) Primarily excreted in urine Half life 20-40 minutes Misoprostol Adverse Effects Abdominal pain, potential for severe diarrhea Nausea/vomiting Headache Rarely cardiovascular effects – MI, arrhythmia, syncope Misoprostol Warnings Must warn patients of potential to cause abortion, not to give to others Misoprostol Drug Interactions Antacids – can increase adverse effects of misoprostol Misoprostol Pregnancy – contraindicated Breastfeeding –use caution, suggestion to take immediately after breastfeeding, next feed 3-4 hours with lower levels in breastmilk Mucosal Protective Agents – Bismuth Compounds Bismuth Subsalicylate (Pepto-Bismol) Indications Diarrhea Dyspepsia Traveler’s Diarrhea Bismuth Subsalicylate Dosing Adult Pediatric – multiple concentrations of oral liquid Renal impairment – no dose adjustment Hepatic impairment – no dose adjustment Bismuth Subsalicylate Mechanism of action o Antisecretory (salicylate) o Antimicrobial (bismuth) o Anti-inflammatory Bismuth Subsalicylate Pharmacokinetic/Pharmacodynamic Factors Converted to bismuth and salicylic acid in GI tract Half life of bismuth 21-72 days, salicylate 2-5 hours Excretion primarily in urine Bismuth Subsalicylate Adverse Effects Esophagitis Melena Anaphylaxis Encephalopathy Tinnitus Bismuth Subsalicylate Warnings Can be neurotoxic when used in very large doses Absorbs x rays, can interfere with diagnostic procedure of GI tract Avoid use in pediatrics who have chickenpox or flu like symptoms to reduce risk of Reye syndrome Bismuth Subsalicylate Contraindications Avoid use in patients with allergy to salicylates, taking other salicylates, those with an ulcer or bleeding problem Bismuth Subsalicylate Drug interactions Aspirin, NSAIDs, SSRIs – these agents have antiplatelet properties, increased risk of bleeding Antidiabetic agents – salicylate enhances hypoglycemic effects ACE Inhibitors – salicylates enhance nephrotoxic effects Corticosteroids – salicylates enhance adverse effects of corticosteroids Bismuth Subsalicylate Pregnancy Avoid use for treatment of dyspepsia, acute diarrhea, or treatment or prevention of traveler’s diarrhea Pregnancy category C; category D in 3rd trimester Breastfeeding Salicylate enters breast milk, use with caution