indication

To assist in labor, elective labor induction, uterine contraction induction

pharmacology

Used to induce labor or to enhance uterine contractions during labor. Uterine motility depends on the formation of the contractile protein actomyosin under the influence of the Ca2+-dependent phosphorylating enzyme myosin light-chain kinase. Oxytocin promotes contractions by increasing the intracellular Ca2+, which in turn activates myosins light chain kinase.. Oxytocin has specific receptors in the muscle llining of the uterus and the receptor concentration increases greatly during pregnancy, reaching a maximum in early labor at term.

mechanism of action

Binds the oxytocin receptor which leads to an increase in intracellular calcium levels. The oxytocin-oxytocin receptor system plays an important role as an inducer of uterine contractions during parturition and of milk ejection.

biotransformation

hepatic oxytocinases

half life

1-6 min

route of elimination

Biliary and renal

drug interactions

Epinephrine: Possible marked increase of arterial pressure

Phenylephrine: Possible marked increase of arterial pressure