Otilonium bromide is a quaternary ammonium derivative with potent antispasmodic and antimuscarinic properties, specifically indicated for the treatment of irritable bowel syndrome (IBS) and other functional gastrointestinal disorders. It acts locally on the smooth muscle of the gastrointestinal tract with minimal systemic absorption, making it a well-tolerated option for long-term management of abdominal pain and discomfort associated with intestinal hypermotility.
Adult: 40 mg to 80 mg twice daily, preferably 20-30 minutes before meals. The usual recommended dose is 40 mg twice daily.
Note: Tablet should be swallowed whole with a glass of water, do not crush or chew. Take 20-30 minutes before breakfast and dinner for optimal effect on postprandial symptoms. Can be taken with or without food, but taking before meals is preferred.
Otilonium bromide exerts a direct relaxant effect on gastrointestinal smooth muscle through multiple mechanisms. It is a non-competitive antagonist of muscarinic receptors (M1 and M3 subtypes) and a blocker of L-type calcium channels. It also inhibits the influx of calcium ions induced by tachykinins (like substance P) and counteracts the contractile response mediated by acetylcholine and histamine. This multi-modal action normalizes intestinal motility and reduces visceral hypersensitivity.
Pregnancy: Category C: Animal studies are insufficient. Use only if potential benefit justifies potential risk to the fetus. Not recommended during pregnancy unless clearly needed.
Driving: May cause dizziness, blurred vision, or drowsiness. Patients should not drive or operate heavy machinery until they know how the medication affects them.
| Other Anticholinergics (e.g., Atropine, Dicyclomine, Tricyclic Antidepressants) | Additive anticholinergic side effects (dry mouth, constipation, urinary retention, blurred vision). | Moderate |
| Metoclopramide, Domperidone | Pharmacological antagonism; otilonium may reduce the prokinetic effect of these drugs. | Moderate |
| Opioid Analgesics (e.g., Morphine, Codeine) | Increased risk of severe constipation and paralytic ileus. | Moderate |
| Potassium Chloride tablets (solid oral dosage forms) | Otilonium may reduce GI motility, increasing risk of mucosal injury from potassium chloride. | Moderate |
| Digoxin | Theoretical risk of increased digoxin absorption due to reduced GI motility; monitor digoxin levels. | Minor |