Estrogen (medication)
Estradiol, estrone, and estriol have all been approved as pharmaceutical drugs and are used medically. Estetrol is currently under development for medical indications, but has not yet been approved in any country. A variety of synthetic estrogen esters, such as estradiol valerate, estradiol cypionate, estradiol acetate, estradiol benzoate, estradiol undecylate, and polyestradiol phosphate, are used clinically. The aforementioned compounds behave as prodrugs to estradiol, and are much longer-lasting in comparison when administered by intramuscular or subcutaneous injection. Esters of estrone and estriol also exist and are or have been used in clinical medicine, for example estrone sulfate (e.g., as estropipate), estriol succinate, and estriol glucuronide (as Emmenin and Progynon).
Estradiol cypionate
Estradiol cypionate, sold under the brand name Depo-Estradiol among others, is an estrogen medication which is used in hormone therapy for menopausal symptoms and low estrogen levels in women, in hormone therapy for transgender women, and in hormonal birth control for women. It is given by injection into muscle once every 1 to 4 weeks.
Side effects of estradiol cypionate include breast tenderness, breast enlargement, nausea, headache, and fluid retention. Estradiol cypionate is a synthetic estrogen and hence is an agonist of the estrogen receptor (ER), the biological target of estrogens like estradiol. Estradiol cypionate is an estrogen ester and a long-lasting prodrug of estradiol in the body. Because of this, it is considered to be a natural and bioidentical form of estrogen.
Estradiol cypionate was first described as well as introduced for medical use in 1952. Along with estradiol valerate, it is one of the most commonly used esters of estradiol. Estradiol cypionate has mostly been used in the United States, but is also marketed in a few other countries. It is not currently available as a generic medication in the United States.