Drospirenone

Drospirenone is a synthetic progesterone derivative used in some hormonal contraceptives and hormone replacement therapies. When used as a contraceptive, it is administered either in combination with an estrogen or as a monopreparation in the form of the so-called mini-pill. Other uses include the treatment of moderate acne vulgaris and the symptomatic treatment of premenstrual dysphoric disorder. It is taken perorally in the form of a tablet.

It was originally developed by Schering AG in the 1970s and has been on the market since the 2000s.

Pharmacodynamics and mechanism of action

Drospirenone acts similarly to natural progesterone. It decreases the effect of estrogens on the endometrium and suppresses follicular maturation and ovulation. It also has aldosterone antagonist properties, meaning that it inhibits the production of aldosterone, a hormone that regulates sodium and potassium levels in the body.

Pharmacokinetics

The drug is rapidly absorbed. The absolute bioavailability of drospirenone is approximately 76% due to the first-pass effect. The maximum plasma concentration of drospirenone occurs within 1 to 2 hours after oral administration. Drospirenone is approximately 95% to 97% bound to serum plasma proteins, primarily albumin. Drospirenone is extensively metabolized in the liver. The serum half-life of drospirenone is estimated to be 30 hours.

Drug Interactions

Interactions occur mainly with concomitant use with inducers or inhibitors of cytochrome P450 enzymes involved in the metabolism of drospirenone. These include, for example, ketoconazole.

Side effects

Possible side effects after taking drospirenone include:

• Dizziness
• nausea
• headache
• chest pain
• gastrointestinal discomfort
• Weight gain
• mood swings
• skin rashes
• acne
• decreased libido

Less commonly, it may also increase the risk of thromboembolism, especially in women who smoke or are over 35 years of age. For this reason, drospirenone is contraindicated in women with a history of thromboembolism or other risk factors for thromboembolism.