Question

Clomiphene is the drug of choice for first line treatment of anovulatory dysfunction (where the ovaries do not release an oocyte during the menstrual cycle) for a variety of reasons. It is orally administered, has few side effects, is easily available and is inexpensive. It acts as a selective estrogen receptor modulator to induce ovulation. In the hypothalamus and anterior pituitary gland, endogenous estrogen causes negative feedback inhibition in that it decreases release of follicle stimulating hormone. Clomifene is structurally similar to estrogen and works by blocking the negative feedback inhibition which results in increased release of follicle stimulating hormone that stimulates follicle growth resulting in ovulation. In the hypothalamus and anterior pituitary gland, what is the mechanism of action of clomiphene? an ion channel inhibitor a transporter inhibitor a receptor agonist a transporter activator an ion channel activator an enzyme inhibitor a receptor antagonist an enzyme activator

Answer 1

Answer:

A receptor antagonist

Reason: Clomiphene is a receptor agonist and receptor antagonist according to the site of action. Clomiphene inhibits the estrogen receptors in hypothalamus to stimulate the pituitary gland to release more LH and FSH for the ovulation.