Estradiol cypionate

Estradiol Cypionate (ECP), also known as depo-estradiol, is a synthetic, steroidal estrogen and estrogen ester – specifically, the 3-cyclopentylpropionate ester of estradiol – which is used in hormone therapy for menopausal symptoms and in hormonal contraception. It is a long-acting form of estradiol, which is the major and most potent naturally occurring estrogen in humans. Estradiol cypionate is administered via intramuscular injection and provides a sustained release of estradiol into the bloodstream for several weeks.

Medical Uses

Estradiol cypionate is primarily used in hormone replacement therapy (HRT) for menopausal symptoms such as hot flashes, vaginal atrophy, and osteoporosis. It is also used in feminizing hormone therapy for transgender women, as part of the medical transition process. In addition, it has applications in hormonal contraception, although it is less commonly used for this purpose compared to other forms of estrogen.

Pharmacology

Mechanism of Action

Estradiol cypionate acts by binding to and activating the estrogen receptor (ER), which is found in various tissues throughout the body. This activation influences the transcription of genes that regulate the development and maintenance of female sexual characteristics, bone metabolism, and various other physiological processes.

Pharmacokinetics

Following intramuscular injection, estradiol cypionate is slowly absorbed into the bloodstream, providing a sustained release of estradiol. Its long-acting nature is due to the esterification of estradiol with cypionate, which slows its release and prolongs its action. The ester is eventually hydrolyzed, releasing active estradiol.

Adverse Effects

The adverse effects of estradiol cypionate are similar to those of other estrogen therapies and may include nausea, breast tenderness, headache, and an increased risk of thromboembolic events, such as deep vein thrombosis (DVT) and pulmonary embolism. Long-term use of estrogens has also been associated with an increased risk of endometrial cancer, which can be mitigated by the concurrent use of a progestogen in women with intact uteruses.

Contraindications

Estradiol cypionate is contraindicated in individuals with known hypersensitivity to estradiol or any component of the formulation, as well as in those with a history of estrogen-dependent tumors, active thromboembolic disease, or undiagnosed vaginal bleeding.

See Also

• Estrogen
• Hormone replacement therapy
• Transgender hormone therapy
• Estrogen ester