Gastrointestinal
53 drugs
5-HT3 receptor antagonists (setrons)
- About this sectionAntiemetics that block serotonin's 5-HT3 receptor on gut nerves and in the brainstem. First line for…
- GranisetronSerotonin 5-HT3A receptor
- OndansetronSerotonin 5-HT3A receptor
- PalonosetronSerotonin 5-HT3A receptor
5-HT4 receptor agonist prokinetics
- About this sectionDrugs that stimulate serotonin 5-HT4 receptors in the gut wall to release acetylcholine and push stool…
- PrucaloprideSerotonin 5-HT4 receptor on enteric neurons
Aminosalicylates (5-ASA)
- About this sectionAnti-inflammatory medicines that deliver 5-aminosalicylic acid to the inflamed bowel. A base treatment for…
- BalsalazideLocal anti-inflammatory action of mesalazine on the colonic mucosa (cyclooxygenase and lipoxygenase products)
- MesalazineColonic mucosa (local anti-inflammatory action)
- OlsalazineLocal anti-inflammatory action of mesalazine on the colonic mucosa
- SulfasalazineColonic mucosa (5-ASA) and immune cells (anti-inflammatory and immunomodulatory effects)
Antacids
- About this sectionBases that neutralise acid already in the stomach. They relieve heartburn quickly but have been replaced by…
- Aluminium hydroxideGastric acid (H⁺) in the stomach lumen
- Calcium carbonateGastric acid (H⁺) in the stomach lumen
- Magnesium hydroxideGastric acid (H⁺) in the stomach lumen; water in the bowel
- SimethiconeSurface tension of gas bubbles in the gut (no receptor)
Antidiarrhoeals
- About this sectionMedicines that slow the gut or reduce intestinal secretion to control diarrhoea. They never replace fluids…
- Diphenoxylate and atropineμ-opioid receptors of the gut wall
- Loperamideμ-opioid receptor of the myenteric plexus
Antimuscarinics (anticholinergics)
- About this sectionDrugs that block acetylcholine at muscarinic receptors: they dry secretions, speed the heart, relax the gut…
- AtropineMuscarinic acetylcholine receptors (M1 to M5)
- DicycloverineMuscarinic acetylcholine receptors of gut smooth muscle
- GlycopyrroniumMuscarinic acetylcholine receptors (M1 to M5)
- Hyoscine butylbromideMuscarinic acetylcholine receptors of smooth muscle (mainly M3)
- Hyoscine hydrobromide (scopolamine)Muscarinic acetylcholine receptors (M1 to M5)
Bile acids
- About this sectionBile acids given as medicines to change the make-up of bile: they dissolve some cholesterol gallstones and…
- Obeticholic acidFarnesoid X receptor (FXR, bile acid receptor)
- Ursodeoxycholic acidBile composition (cholesterol saturation and bile acid pool)
Cannabinoids (medical antiemetics and appetite stimulants)
- About this sectionSynthetic THC and related drugs that act on cannabinoid receptors. Reserved for chemotherapy vomiting that…
- DronabinolCannabinoid receptor 1 (CB1)
- NabiloneCannabinoid receptor 1 (CB1)
Dopamine-antagonist antiemetics and prokinetics
- About this sectionDrugs that block dopamine D2 receptors in the vomiting centre and, some of them, speed up the stomach…
- DomperidoneDopamine D2 receptor
- DroperidolDopamine D2 receptor (chemoreceptor trigger zone)
- MetoclopramideDopamine D2 receptor
- ProchlorperazineDopamine D2 receptor
Drugs for irritable bowel syndrome
- About this sectionGut-targeted drugs for IBS with diarrhoea: a 5-HT3 blocker (alosetron) and a mixed opioid-receptor drug…
- Alosetron5-HT3 receptor (ligand-gated cation channel) on enteric neurons
- EluxadolineMu and kappa opioid receptors (agonist), delta opioid receptor (antagonist) in the gut
GLP-2 analogues
- About this sectionInjected versions of the gut hormone GLP-2 that make the intestinal lining grow, so a short bowel absorbs…
- TeduglutideGlucagon-like peptide-2 receptor (GLP-2R)
H2 receptor antagonists (H2 blockers)
- About this sectionAcid reducers that block histamine at the parietal cell's H2 receptor. Weaker than PPIs; ranitidine was…
- CimetidineHistamine H2 receptor
- FamotidineHistamine H2 receptor
Laxatives
- About this sectionMedicines that soften stool or speed up the bowel. They work by drawing in water, coating stool, stimulating…
- AlvimopanMu-opioid receptor in the gut (peripheral antagonist)
- BisacodylEnteric nervous system and colonic mucosa
- Docusate sodiumStool surface (surfactant action) and intestinal mucosa
- LactuloseColonic contents (osmotic effect and ammonia trapping by colonic bacteria)
- LinaclotideGuanylate cyclase C (GC-C) on the luminal surface of intestinal cells
- LubiprostoneClC-2 chloride channel on the apical membrane of intestinal cells
- Macrogol (polyethylene glycol)Colonic lumen (osmotic water retention)
- Methylnaltrexoneμ-opioid receptors of the gut (peripheral)
- NaloxegolMu-opioid receptor in the gut (peripherally restricted antagonist)
- PlecanatideGuanylate cyclase C (GC-C) on intestinal epithelium
- SennaColonic mucosa and enteric nervous system
Mucosal protectants (sucralfate and bismuth)
- About this sectionDrugs that coat or protect the stomach lining instead of lowering acid. Sucralfate seals ulcers; bismuth…
- Bismuth subsalicylateGut mucosa and microbes (local action)
- SucralfateProteins of the ulcer base (local physical barrier)
NK1 receptor antagonists
- About this sectionAntiemetics that block substance P at brain NK1 receptors. Added to a setron and dexamethasone, they prevent…
- AprepitantTachykinin receptor 1 (NK1, substance P receptor)
- FosaprepitantTachykinin receptor 1 (NK1, substance P receptor)
- Netupitant and palonosetronNeurokinin-1 (substance P) receptor, plus the 5-HT3 receptor (palonosetron)
Potassium-competitive acid blockers (P-CABs)
- About this sectionAcid blockers that bind the proton pump at its potassium site, reversibly and without needing acid…
- VonoprazanGastric H+/K+-ATPase (proton pump), potassium-binding site
Proton pump inhibitors (PPIs)
- About this sectionThe strongest acid reducers: they switch off the stomach's acid pump itself, so they work whatever triggers…
- EsomeprazoleGastric H⁺/K⁺-ATPase (proton pump), α subunit
- LansoprazoleGastric H⁺/K⁺-ATPase (proton pump), α subunit
- OmeprazoleGastric H⁺/K⁺-ATPase (proton pump), α subunit
- PantoprazoleGastric H⁺/K⁺-ATPase (proton pump), α subunit
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Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given.
Representative model, for educational purposes only.