Pharmacology

Question 1

What is the mechanism of action of mifepristone?

Answer 1

Mifepristone is a steroidal anti-progesterone
It is a competitive progesterone receptor antagonist
Progesterone is required for ongoing trophoblast proliferation
- causes decidual degeneration
- trophoblast detachment
- increases sensitivity of the myometrium to the contractile effect of prostaglandin

Question 2

What is the mechanism of action of misoprostol?

Answer 2

prostaglandin analogue that binds to and stimulates the Prostaglandin E1receptors
- resulting in cervical softening and dilation and uterine contraction