Drospirenone is an agonist of the PR, the biological target of progestogens like progesterone. It has about 35% of the affinity of promegestone for the PR and about 19 to 70% of the affinity of progesterone for the PR. Drospirenone has antigonadotropic and functional antiestrogenic effects as a result of PR activation. The ovulation-inhibiting dosage of drospirenone is 2 to 3 mg/day. Inhibition of ovulation occurred in about 90% of women at a dose of 0.5 to 2 mg/day and in 100% of women at a dose of 3 mg/day. The total endometrial transformation dose of drospirenone is about 50 mg per cycle, whereas its daily dose is 2 mg for partial transformation and 4 to 6 mg for full transformation. The medication acts as a contraceptive by activating the PR, which suppresses the secretion of luteinizing hormone, inhibits ovulation, and alters the cervical membrane and endometrium.
Due to its antigonadotropic effects, drospirenone inhibits the secretion of the gonadotropins, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and suppresses gonadal sex hormone production, including of estradiol, progesterone, and testosterone. Drospirenone alone at 4 mg/day has been found to suppress estradiol levels in premenopausal women to about 40 to 80 pg/mL depending on the time of the cycle. No studies of the antigonadotropic effects of drospirenone or its influence on hormone levels appear to have been conducted in men. In male cynomolgus monkeys however, 4 mg/kg/day oral drospirenone strongly suppressed testosterone levels.