Fispemifene

Fispemifene is a synthetic steroid and selective estrogen receptor modulator (SERM) that is used in the treatment of male hypogonadism and osteoporosis in men. It is a nonsteroidal antiestrogen that is similar in structure and action to tamoxifen and raloxifene.

Mechanism of Action

Fispemifene acts as an antagonist at estrogen receptors in some tissues and as an agonist in others. In the prostate and breast, it acts as an antagonist, inhibiting the growth-promoting effects of estrogen. In bone and lipid metabolism, it acts as an agonist, mimicking the beneficial effects of estrogen.

Clinical Use

Fispemifene is used in the treatment of male hypogonadism, a condition characterized by low levels of testosterone and symptoms such as fatigue, depression, and sexual dysfunction. It is also used in the treatment of osteoporosis in men, a condition characterized by low bone mass and increased risk of bone fractures.

Side Effects

Common side effects of fispemifene include hot flashes, nausea, and vomiting. Less common side effects include breast pain, joint pain, and insomnia.

Pharmacokinetics

Fispemifene is well absorbed after oral administration and is extensively metabolized in the liver. It has a half-life of approximately 8 hours and is excreted primarily in the urine.

See Also

• Selective estrogen receptor modulator
• Male hypogonadism
• Osteoporosis