Antispasmodic, quaternary ammonium belladonna alkaloid
ATC code: A03BB01 (Hyoscine butylbromide)
A semisynthetic quaternary ammonium derivative of scopolamine. Blocks muscarinic M1, M2, M3 receptors in GI and urogenital smooth muscle. Unlike atropine and scopolamine, does not cross the blood-brain barrier – no central anticholinergic effects (drowsiness, confusion, memory impairment). Oral systemic bioavailability under 1% – action is mostly local. Widely used in Spain under the Buscapina brand.
First line
First-line for acute functional spasmodic abdominal pain per NG61 (2017) and WGO 2023. Dose 10–20 mg 3–4 times daily orally or 20 mg IM/IV in severe colic. Annaházi 2014 meta-analysis showed moderate efficacy over placebo with low certainty. Short course – usually 1–3 days; persistent pain needs evaluation.
Second line
Used as-needed for IBS pain episodes. Not first-line – inferior to mebeverine, otilonium bromide, and pinaverium bromide in effect duration.
The drug is promoted for these uses outside international guidelines. Each entry below is analyzed against AEMPS, FDA, EMA, Cochrane and major RCTs.
Not recommended
Hyoscine butylbromide is prescribed for any abdominal discomfort and stress-related PMS spasm. NG121 and 2022 confine hyoscine to confirmed functional GI spasm disorders. Long-term use causes anticholinergic effects (dry mouth, tachycardia, urinary retention, glaucoma worsening).
Opens the checker prefilled with this drug. Pick the second one from your regimen.
Large pregnancy data set without described teratogenic effects. Safe in T1, T2, T3 when indicated.
Compatible with breastfeeding. Systemic bioavailability is low.
Reference information, not a clinical decision. Discuss feeding pauses or changes with your physician or an IBCLC.
Hyoscine butylbromide is evaluated for the following indications with varying evidence strength: Gastrointestinal smooth muscle spasm (evidence tier B), Irritable bowel syndrome (evidence tier B), Biliary dyskinesia (evidence tier F). See the full indication matrix with dosing and citations above on this page.
Common side effects of Hyoscine butylbromide (≥ 1 in 100): Dry mouth, Tachycardia, Constipation, Blurred vision (rare with low bioavailability), Urinary retention in predisposed patients. See the Safety section for uncommon and serious reactions.
FDA category C. Large pregnancy data set without described teratogenic effects. Safe in T1, T2, T3 when indicated.
Compatible with breastfeeding. Systemic bioavailability is low.
Hyoscine butylbromide is contraindicated in: Hypersensitivity to hyoscine or belladonna derivatives; Angle-closure glaucoma; Myasthenia gravis; Megacolon; Pyloric stenosis. Full list in the Safety section.