Subcutaneous injection
Estradiol cypionate in a microcrystalline aqueous suspension has been found to have equivalent effectiveness and virtually identical pharmacokinetics when administered by subcutaneous injection versus intramuscular injection. However, subcutaneous injection is considered to be easier and less painful relative to intramuscular injection, and for these reasons, may result in comparatively greater satisfaction and compliance. Chemistry
Estradiol cypionate is a synthetic estrane steroid and the C17β cyclopentylpropionate (cypionate) fatty acid ester of estradiol. It is also known as estra-1,3,5(10)-triene-3,17β-diol 17β-cyclopentylpropionate. Other common esters of estradiol in use include estradiol valerate, estradiol enantate, and estradiol acetate, the former two of which are C17β esters of estradiol similarly to estradiol cypionate and the latter of which is the C3 acetate ester of estradiol. The experimental octanol/water partition coefficient (logP) of estradiol cypionate is 6.9. History
Estradiol cypionate was patented by Upjohn in 1952, with a priority date of 1951. It was first introduced for medical use by Upjohn in 1952 under the brand name Depo-Estradiol in the United States. Subsequently, it was also marketed in other countries such as European countries and Japan. The first clinical reports of estradiol cypionate were published in 1952 and thereafter. It was initially known as estradiol cyclopentylpropionate (ECP), and did not become known as estradiol cypionate until over a decade later in the mid-to-late 1960s.
Estradiol cypionate is not available in Canada, although it is marketed in several veterinary formulations in this country.Estradiol cypionate is available in Taiwan in combination with testosterone cypionate. It is also available as a combined injectable contraceptive in combination with medroxyprogesterone acetate in at least 18 countries, mostly in Latin America and Southeast Asia. Estradiol cypionate/testosterone cypionate and estradiol cypionate/medroxyprogesterone acetate were both formerly marketed in the United States, but have been discontinued in this country. See also
Estradiol cypionate/medroxyprogesterone acetate
Estradiol cypionate/testosterone cypionate


== References ==