Digestive / GI

Irreversibly shut off the stomach’s acid pump — the most powerful acid suppressors. Take before the first meal; think about long-term effects and the clopidogrel interaction.

Block the serotonin (5-HT3) trigger that drives vomiting from chemo, radiation, and surgery. A key risk is ondansetron’s dose-dependent QT prolongation.

Block the histamine (H2) arm of acid secretion — milder and faster than PPIs but shorter-acting and prone to tolerance. Famotidine is now one of the most commonly used agents; cimetidine has many interactions.

Promote elimination by several distinct mechanisms. The universal nursing rule: rule out bowel obstruction before giving any laxative.

Neutralize stomach acid for fast, short heartburn relief. Separate from other drugs; mind the bowel effects.

Slow the gut to control diarrhea — but rule out infection first. High-dose loperamide is cardiotoxic.

Locally acting anti-inflammatories that induce and maintain remission in inflammatory bowel disease. Sulfasalazine’s sulfa half drives its side effects.

Anticholinergics that relax gut smooth muscle to ease cramping in IBS. The side-effect profile is essentially anticholinergic — can’t see, can’t spit, can’t pee, can’t poop.