Estradiol enantate
Estradiol enantate, sold under the brand names Perlutal and Topasel among others, is an estrogen medication which is used in hormonal birth control. It is formulated in combination with dihydroxyprogesterone acetophenide (DHPA; algestone acetophenide), a progestin, and is used as a combined injectable contraceptive. Estradiol enantate is not available alone. The medication is given by injection into muscle once a month.
Side effects of estradiol enantate include breast tenderness, breast enlargement, nausea, headache, and fluid retention. The drug is a synthetic estrogen and hence is an agonist of the estrogen receptor (ER), the biological target of estrogens like estradiol. Estradiol enantate 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 enantate was first described by 1954, and was first studied in combination with DHPA as a combined injectable contraceptive in 1964. The combination was introduced for clinical use by the mid-1970s. Estradiol enantate is not available as a standalone medication (i.e., by itself without DHPA). The combination is available in Latin America and Hong Kong, and was also previously marketed in Spain and Portugal.
Estradiol (medication)
Estradiol was first isolated in 1935. It was also originally known as "dihydroxyestrin" or "alpha-estradiol". It was first marketed, as estradiol benzoate, in 1936. Estradiol was also marketed in the 1930s under brand names such as Progynon-DH, Ovocylin, and Dimenformon. Micronized estradiol, via the oral route, was first evaluated in 1972, and this was followed by the evaluation of vaginal and intranasal micronized estradiol in 1977. Oral micronized estradiol was first approved in the United States under the brand name Estrace in 1975.
In 1931, Butenandt found that the benzoic acid ester of estrone had a prolonged duration of action. Subsequently, Schwenk and Hildebrant synthesized estradiol benzoate from estradiol in 1933, and estradiol benzoate was introduced by Schering-Kahlbaum for medical use via intramuscular injection under the brand name Progynon-B in 1936. It was the first estrogen ester to be marketed, and has since been followed by many additional esters, for instance estradiol valerate and estradiol cypionate in the 1950s. Ethinylestradiol was synthesized from estradiol by Inhoffen and Hohlweg in 1938 and was introduced for oral use by Schering in the United States under the brand name Estinyl in 1943. It remains widely used in combined oral contraceptives.