Bricanyl Mechanism of Action

Pharmaco-therapeutic group: selective β₂-agonist, terbutaline. ATC code: R03C C03.
Pharmacology: Pharmacodynamics: Terbutaline is an adrenergic agonist which predominantly stimulates β₂-receptors, thus producing relaxation of bronchial smooth muscle, inhibition of the release of endogenous spasmogens, inhibition of edema caused by endogenous mediators, increased mucociliary clearance and relaxation of the uterine muscle.
The bronchodilating effect of Terbutaline sulfate (BRICANYL) tablets has in clinical trials been shown to have a duration for up to 8 hours.
Pharmacokinetics: There is a considerable first-pass metabolism in the intestinal wall and in the liver. The bioavailability is about 10% and increases to about 15% if terbutaline is taken on an empty stomach. Maximum plasma concentration of terbutaline is reached within 3 hours. Terbutaline is metabolized mainly by conjugation with sulphuric acid and excreted as the sulfate conjugate. No active metabolites are formed.
Toxicology: Preclinical safety data: The major toxic effect of terbutaline, observed in toxicological studies, is focal myocardial necrosis. This type of cardiotoxicity is a well-known class-effect, and the effect of terbutaline is similar to or less pronounced than that of other beta-receptor agonists. Terbutaline has been used extensively over many years for the relief of bronchospasm without identifying any areas of concern.