Description
Prostaglandin E1 PGE1 exerts a number of effects, including systemic vasodilation, inhibition of platelet aggregation, and stimulation of intestinal motility. PGE1 relaxes isolated smooth muscle cells contracted by norepinephrine. It has become widely used in the treatment of ED. Alprostadil binds with PGE receptors and results in a cyclic adenosine monophosphate (cAMP) mediated smooth muscle relaxation. Little is known about the pharmacokinetics of PGE1, but it is believed that as much as 80% is metabolized in one pass through the lungs. Such rapid degradation probably accounts for its lack of significant cardiovascular side effects when administered intracavernosally. PGE1 can also be metabolized in the penis.

Usage:
1. Alprostadil is used in maintaining a patent ductus arteriosus in newborns.
2. Alprostadil is also as urethral suppositories and in injectable form.
3. Alprostadil is also used for critical limb ischemia.