Pharmacology: Pharmacodynamics: Fucon Solution for Injection 20mg/ml is an antispasmodic agent which relaxes smooth muscle of the organs of the abdominal and pelvic cavities. It is believed to act predominantly on the intramural parasympathetic ganglia of these organs.
Pharmacokinetics: Absorption and distribution: After intravenous administration hyoscine butylbromide is rapidly distributed (t½α = 4 min, t½β = 29 min) into the tissues. The volume of distribution (Vss) is 128 L (corresponding to approx. 1.7 L/kg). Because of its high affinity for muscarinic receptors, hyoscine butylbromide is mainly distributed on muscle cells of the abdominal and pelvic area as wells as in the intramural ganglia of the abdominal organs. Plasma protein binding (albumin) of hyoscine butylbromide is approximately 4.4%. Hyoscine butylbromide (1mM) has been observed to interact with choline transport (1.4 nM) in epithelial cells of human placenta in vitro.
Metabolism and elimination: The main metabolic pathway is the hydrolic cleavage of the ester bond. The half-life of the terminal elimination phase (t½γ) is approximately 5 hours. The total clearance is 1.2 L/min. The portion of unchanged active ingredient excreted in the urine is approximately 50%. The metabolites excreted via the renal route bind poorly to the muscarinic receptors and are therefore not considered to contribute to the effect of the hyoscine butylbromide.
Pediatric population: No particular pharmacokinetic studies hyoscine butylbromide have been performed in children.