Overview
Hyoscine N-butylbromide is an antispasmodic and anticholinergic medication used primarily for the treatment of abdominal cramps, spasms, and pain associated with gastrointestinal and biliary disorders. It acts as a competitive antagonist at muscarinic acetylcholine receptors, particularly in the smooth muscle of the gastrointestinal tract, biliary system, and genitourinary tract, leading to relaxation of smooth muscle and reduction of spasmodic pain.
Mechanism of Action
Competitive antagonist of muscarinic acetylcholine receptors (M1, M2, M3 subtypes) in smooth muscle of the gastrointestinal tract, biliary system, and genitourinary tract. It inhibits acetylcholine binding, reducing smooth muscle contraction and glandular secretions, thereby relieving spasms and associated pain. It has minimal central nervous system effects due to poor blood-brain barrier penetration.
Indications
- Symptomatic relief of abdominal cramps and pain associated with irritable bowel syndrome (IBS)
- Treatment of biliary colic and spasms of the biliary tract
- Relief of spasms in the genitourinary tract (e.g., renal colic, dysmenorrhea)
- Adjunctive therapy in diagnostic procedures (e.g., endoscopy) to reduce gastrointestinal motility
Dosage
Adults: Typically 10-20 mg orally 3-4 times daily as needed for spasmodic pain. Maximum daily dose should not exceed 80 mg. For acute spasms, may be administered intramuscularly or intravenously under medical supervision. Dosage may vary based on condition and patient response; follow prescribing information or healthcare provider instructions.
Contraindications
- Hypersensitivity to hyoscine N-butylbromide or any component of the formulation
- Glaucoma (particularly narrow-angle glaucoma)
- Prostatic hypertrophy with urinary retention
- Mechanical gastrointestinal obstruction (e.g., paralytic ileus)
- Severe ulcerative colitis or toxic megacolon
- Myasthenia gravis
Side Effects
- Dry mouth
- Blurred vision
- Tachycardia (increased heart rate)
- Dizziness or drowsiness
- Constipation
- Urinary retention
- Nausea or vomiting
- Allergic reactions (e.g., rash, itching)
Interactions
- Other anticholinergic drugs (e.g., atropine, tricyclic antidepressants) may enhance adverse effects
- May reduce absorption of other oral medications due to decreased gastrointestinal motility
- Concomitant use with CNS depressants (e.g., alcohol, benzodiazepines) may increase sedation
- May antagonize effects of prokinetic agents (e.g., metoclopramide)