Drospirenone/ethinyl estradiol.

Drospirenone 3 mg/ethinyl estradiol 20 microg (24/4) is a new unique oral contraceptive formulation that combines in a novel dosing regimen the lowest dosage of ethinyl estradiol commonly used today with drospirenone, an innovative progestin. Drospirenone is a compound closely resembling progesterone, but with the antimineralocorticoid and antiandrogenic properties of a related therapeutic agent, the diuretic, antihypertensive and androgen receptor antagonist, 17alpha-spironolactone. The prolongation of hormonally active pills in the monthly drospirenone/ethinyl estradiol cycle from 21 days to 24 days, followed by 4 days of inactive pills, is an interesting variant of the recently developed extended pill regimens (1).