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.
Estriol (medication)
A variety of analogues of estriol are known, including both naturally occurring isomers and synthetic substituted derivatives and esters. 16β-Epiestriol (epiestriol), 17α-epiestriol, and 16β,17α-epiestriol are isomers of estriol that are endogenous weak estrogens. Mytatrienediol (16α-methyl-16β-epiestriol 3-methyl ether) is a synthetic derivative of 16β-epiestriol that was never marketed. Estriol acetate benzoate, estriol succinate, and estriol tripropionate are synthetic estriol esters that have been marketed for medical use, whereas estriol dihexanoate, estriol dipropionate, and estriol triacetate have not been introduced. Quinestradol is the 3-cyclopentyl ether of estriol and has also been marketed. Polyestriol phosphate, an ester of estriol in the form of a polymer, has been marketed previously as well. These esters, ethers, and polymers are prodrugs of estriol. Ethinylestriol and nilestriol are synthetic C17α ethynylated derivatives of estriol. Ethinylestriol has not been marketed, but nilestriol, which is the 3-cyclopentyl ether of ethinylestriol and a prodrug of it, has been.