N-Butylscopolammonium Bromide (Butylscopolamine Bromide) 95
N-Butylscopolammonium Bromide (Butylscopolamine Bromide) en-byoo-til-skoe-pahl’ah-moe-nee-um broe’mide Trade and other names: Buscopan Functional classification: Antispasmodic
Pharmacology and Mechanism of Action Antispasmotic, antimuscarinic, anticholinergic drug. This is a quarternary ammonium compound derived from belladonna alkaloid. Butylscopolamine, like other antimuscarinic drugs, blocks cholinergic receptors and produces a parasympatholytic effect. It affects receptors throughout the body, but it is used more commonly for its gastrointestinal effects. It effectively inhibits secretions and motility of the gastrointestinal tract by blocking parasympathetic receptors. It has a short half-life (15-25 minutes) and short duration of action. As a quarternary ammonium compound, it typically does not cross the blood–brain barrier to produce central nervous system reactions.
Indications and Clinical Uses Butylscopolamine bromide is indicated for treating pain associated with spasmodic colic, flatulent colic, and intestinal impactions in horses. It is also used to relax the rectum and reduce intestinal strain to facilitate diagnostic rectal palpation. This agent also relieves bronchoconstriction caused by airway smooth muscle contraction mediated by vagal activation of muscarinic receptors.
Precautionary Information Adverse Reactions and Side Effects Adverse reactions from anticholinergic drugs are related to their blocking of acetylcholine receptors and producing a systemic parasympatholytic response. As expected with this class of drugs, animals will have increased heart rate, decreased secretions, dry mucous membranes, decreased gastrointestinal tract motility, and dilated pupils. The effects on intestinal motility usually have less than 2 hours’ duration. In target animal safety studies in which doses of 1, 3, and 5 times the approved dose and up to 10 times the dose were administered to horses, the clinical signs described previously were observed. However, at high doses there were no CBC or biochemical abnormalities or lesions identified at necropsy. Contraindications and Precautions N-butylscopolammonium bromide will decrease intestinal motility. Use cautiously in conditions where decreased motility will be a concern. Drug Interactions N-butylscopolammonium bromide is an anticholinergic drug and therefore will antagonize any other medications that are intended to produce a cholinergic response (e.g., metoclopramide).
Instructions for Use Experience is limited to treating spasmodic colic, flatulent colic, and intestinal impactions in horses. There is no experience in other animals.
Patient Monitoring and Laboratory Tests Monitor equine intestinal motility (gut sounds and fecal output) during treatment. Monitor heart rate in treated animals.
96 N-Butylscopolammonium Bromide (Butylscopolamine Bromide)
Formulations • N-butylscopolammonium is available in a 20-mg/mL solution.
Stability and Storage Store in a tightly sealed container, protected from light, and at room temperature.
Small Animal Dosage • No dose is reported for small animals.
Large Animal Dosage Horses • 0.3 mg/kg, slowly IV as a single dose (1.5 mL per 100 kg). Onset of action is usually within 2 minutes, with a duration of less than 2 hours. • To relieve bronchoconstriction: 0.3 mg/kg IV, single dose
Regulatory Information Do not administer to animals intended for food.