Duvadilan Mechanism of Action

Pharmacology: Pharmacodynamics: Pharmacodynamic effects: Isoxsuprine has a strong inhibitory effect on the muscular tissue of uterus and blood vessels. It has only a moderate effect on the smooth muscle of the respiratory, biliary and intestinal tracts. The effects of isoxsuprine are brought about mainly by its influence on the receptors in those organs responsive to stimuli from the sympathetic nervous system. Isoxsuprine hydrochloride is a beta-adrenergic receptor stimulator. Hence it is classified as beta-agonist drug, in particular a uterine relaxant. It is also a vasodilator.
The mechanism of action of isoxsuprine in the treatment of preterm labor is detailed as follows: β-sympathomimetic effect: By virtue of this effect, isoxsuprine has relaxant action on the muscular tissue of the uterus.
α-sympathomimetic effect: Isoxsuprine antagonizes the effects of α-receptor stimulation. Some uterine contraction, which can otherwise occur because of α-receptor stimulation, gets inhibited due to this effect of isoxsuprine.
Direct relaxant action on the smooth muscle fibers: Isoxsuprine induces a direct relaxant action on the smooth muscle fibers and so enhances those effects resulting from its action on the sympathetic receptors.
Pharmacokinetics: Isoxsuprine hydrochloride is well absorbed from the gastro-intestinal tract. The peak plasma concentrations occur one hour after oral administration. Plasma half-life is 1.5 hours.
Isoxsuprine is excreted in urine mainly as conjugates.