Hormonal birth control and hormone therapy for women in menopause are both treatments that rely on synthetic hormones for their activity. One class of synthetic hormones is called progestins, named for their ability to mimic the effects of the hormone progesterone. Drospirenone is a member of the progestin family and is used in preparations for birth control and hormone replacement therapy.
Identification
Drospirenone is a synthetic hormone which is also known as a progestogen. Specifically, it is structurally similar to another hormone, which is called spironolactone. Drospirenone is created for commercial purposes by chemically modifying the chemical androstenolone (via many different chemical steps) to form a compound which is chemically named "6β,7β,15β,16β-dimethylene-3-oxo-17α-pregn-4-ene-21,17 carbolactone."
Drospirenone and Progesterone
Drospirenone is medically useful because of its ability to bind the same receptors as another hormone, progesterone. Receptors are special proteins that can recognize specific hormones. When these receptors are bound they send out a signal to other cells that either activates or inhibits them.
Progesterone
Progesterone is a hormone that helps control the body's menstrual cycle. Progesterone works to prevent premature ovulation and fertilization by preventing eggs from maturing and also by thickening the cervical mucus. As a result, progesterone, or synthetic progestins such as drospirenone, are commonly included in hormonal birth control preparations because high levels can prevent ovulation. Because progesterone is used to regulate a female's menstrual cycle, progesterone levels also fall during menopause.
Formulations
Drospirenone is most commonly used for birth control as well as for hormone replacement therapy for women in menopause. In both cases it is paired with a synthetic estrogen. When used for hormone replacement it is paired with estradiol. When used for birth control, it is paired with a derivative of estradiol, known as ethinyl estradiol.
Side Effects
Drospirenone has been shown to cause increased excretion of sodium in women because it also signals to the kidneys to excrete sodium. It also causes an increase in renin levels (renin is a kidney hormone) as well as the hormone aldosterone (a hormone which acts on the kidneys). Despite this loss of sodium (which normally lowers blood pressure), drospirenone does not cause any changes in blood pressure. It also raises high-density lipoprotein levels (also known as the "good" cholesterol) but also raises overall triglyceride levels.
