Estradiol valerate

The medical uses of estradiol valerate are the same as those of estradiol and other estrogens. Examples of indications for the medication include hormone therapy and hormonal contraception. In regard to the latter, estradiol valerate is available in combination with a progestin as a combined estradiol-containing oral contraceptive (with dienogest) and as a combined injectable contraceptive. Along with estradiol cypionate, estradiol undecylate, and estradiol benzoate, estradiol valerate is used as a form of high-dose estrogen therapy in feminizing hormone therapy for transgender women. It is also used as a form of high-dose estrogen therapy in the treatment of prostate cancer in men. Injectable estradiol valerate has been used to suppress sex drive in sex offenders. In the United States, the approved indications of estradiol valerate injections include the treatment of moderate to severe hot flashes and vaginal atrophy associated with menopause in women, the treatment of hypoestrogenism due to hypogonadism, castration, or primary ovarian failure in women, and the palliative treatment of advanced prostate cancer in men. Elsewhere in the world, oral estradiol valerate is similarly approved for the treatment of symptoms associated with menopause or hypoestrogenism due to castration in women. Such symptoms may include hot flashes, outbreaks of sweat, sleep disturbances, depressive moods, irritability, headaches, and dizziness. Estradiol valerate is usually used in the treatment of advanced prostate cancer in men at a dosage of 30 mg or more every 1 to 2 weeks by intramuscular injection. Available forms Estradiol valerate is and has been available in the form of vials and ampoules of oil solution for intramuscular injection in concentrations of 4, 5, 10, 20, and 40 mg/mL and in the form of oral tablets at doses of 0.5, 1, 2, and 4 mg per tablet. In the United States, it is specifically available in formulations of 10, 20, and 40 mg/mL in oil solution (as Delestrogen, as well as generics). In addition to single-drug formulations, oral estradiol valerate is available in combination with the progestin dienogest as a combined oral contraceptive and intramuscular estradiol valerate is marketed at a concentration of 5 mg/mL in combination with the progestin hydroxyprogesterone caproate and with the progestin norethisterone enantate as combined injectable contraceptives. The availability of estradiol valerate-containing products varies throughout the world. ==Contraindications==

Contraindications of estrogens include coagulation problems, cardiovascular diseases, liver disease, and certain hormone-sensitive cancers such as breast cancer and endometrial cancer, among others. ==Side effects==

The side effects of estradiol valerate are the same as those of estradiol. Examples of such side effects include breast tenderness and enlargement, nausea, bloating, edema, headache, and melasma. High-dose estrogen therapy with estradiol valerate injections may also cause an increased risk of thromboembolism, changes in blood lipid profile, increased insulin resistance, and increased levels of prolactin. ==Overdose==

Estradiol valerate has been used at very high doses of 40 to 100 mg once per week in women and men, without overt signs of acute toxicity observed. Symptoms of estrogen overdosage may include nausea, vomiting, bloating, increased weight, water retention, breast tenderness, vaginal discharge, heavy legs, and leg cramps. These side effects can be diminished by reducing the estrogen dosage. == Interactions ==

Inhibitors and inducers of cytochrome P450 may influence the metabolism of estradiol and by extension circulating estradiol levels. ==Pharmacology==

, the active form of estradiol valerate. Pharmacodynamics Estradiol valerate is an estradiol ester, or a prodrug of estradiol. Oral ethinylestradiol at 10 μg/day has been found to have about 1.5- to 2.5-fold the impact of 2 mg/day oral estradiol valerate on HDL cholesterol and triglycerides. The influence of 20 or 50 μg/day oral ethinylestradiol on coagulation factors and HDL cholesterol is markedly greater than that of 2 mg/day oral estradiol valerate. Estradiol-containing birth control pills, which contain 1 to 3 mg/day estradiol or estradiol valerate, have been found to increase sex hormone-binding globulin (SHBG) levels by 1.5-fold. Oral estradiol valerate at 6 mg/day has been found to increase SHBG levels by 2.5- to 3-fold in transgender women. For comparison, combined birth control pills containing ethinylestradiol and a progestin with minimal androgenic or antiandrogenic activity have been found to increase SHBG levels by about 3- to 4-fold. Pharmacokinetics Regardless of the route of administration, estradiol valerate behaves as a prodrug of estradiol via cleavage by esterases into estradiol and the natural fatty acid valeric acid. This cleavage occurs not only in the liver, but also in the blood and in tissues, and the hydrolysis of estradiol valerate into estradiol and valeric acid is complete regardless of whether the medication is administered orally or parenterally. These concentrations of estradiol and estrone are comparable to those observed with 1 and 2 mg/day oral estradiol. Likewise, other studies found that levels of estradiol and estrone are very similar after oral administration of roughly equimolar doses of estradiol (1.5 mg) and estradiol valerate (2 mg). A study of high-dose oral estradiol valerate found levels of estradiol of about 250 pg/mL after a single 10-mg dose in three women. It has been investigated for this indication, along with vaginal and transdermal estradiol, because oral estradiol valerate is sometimes unable to achieve adequate estradiol levels and hence proper cycle control in this situation. The administration of 2 mg oral micronized estradiol valerate tablets (Progynova, Schering) sublingually 3 or 4 times per day has been found to result in circulating estradiol levels of about 290 pg/mL to 460 pg/mL in premenopausal women (time of measurements not given). Intramuscular injection In contrast to oral administration, the bioavailability of estradiol valerate is complete (i.e., 100%) via intramuscular injection. Upon intramuscular injection of estradiol valerate in an oil solution, the solvent (i.e., oil) is absorbed, and a primary microcrystalline depot is formed within the muscle at the site of injection. A study found that a single intramuscular injection of 5 mg estradiol valerate resulted in peak circulating levels of 667 pg/mL estradiol and 324 pg/mL estrone within approximately 2 and 3 days, respectively. The duration of estradiol valerate at this dose and in this study was considered to be 7 to 8 days. Subcutaneous injection Estradiol esters like estradiol valerate and estradiol cypionate can be given by subcutaneous injection instead of intramuscular injection. Intravenous injection The administration of estradiol valerate by intravenous injection has been studied. It has been found to be very rapidly cleaved into estradiol. The bioavailability and metabolism of estradiol valerate does not differ with intravenous versus intramuscular injection. Conversely, intravenous injection of estradiol valerate has a very short duration, whereas intramuscular injection has a long duration and elimination half-life. ==Chemistry==

plus the fatty acid valeric acid (valerate) equals estradiol valerate, a C17β ester of estradiol. Estradiol valerate is a synthetic estrane steroid and the C17β valerate (pentanoate) fatty acid ester of estradiol. ==History==

Estradiol valerate was patented by Ciba in 1940 and 1941, with a priority date of 1936. It was synthesized and studied, along with a variety of other estradiol esters, by Karl Junkmann of Schering AG in 1953. The medication was first introduced for medical use via intramuscular injection in 1954 by Schering in Europe under the brand name Progynon Depot and by Squibb in the United States under the brand name Delestrogen. In 1966, oral estradiol valerate was introduced by Schering for medical use in Europe under the brand name Progynova. A report of its metabolism was published in 1967. Esterification of estradiol, as in estradiol valerate, has been claimed to improve its metabolic stability with oral administration. In 1968, micronized preparations of oral estradiol valerate were first introduced under the brand names Progynova 21 and Progynova 21 mite. and estradiol cypionate (1952), estradiol valerate is one of the most widely used esters of estradiol. ==Society and culture==

Generic names Estradiol valerate is the generic name of the drug and its , , , and , while oestradiol valerate was formerly its . Brand names Estradiol valerate has been marketed under the brand names Altadiol, Androtardyl-Oestradiol, Ardefem, Climaval, Cyclabil, Cyclocur, Deladiol, Delahormone Unimatic, Delestrogen, Delestrogen 4X, Depogen, Diol-20, Dioval, Ditate, Dura-Estate, Dura-Estradiol, Duratrad, Duragen, Estate, Estra-L, Estradiol Depot, Estraval, Estraval Depot, Estraval PA, Estravel, Femogen, Femogex, Gynogen L.A., Gynokadin, Lastrogen, Menaval, Merimono, Neofollin, Nuvelle, Oestrogynal, Ostrin Depo, Pelanin, Pharlon, Postoval, Primogyna, Primogyn, Primogyn Depot, Progynon, Progynon Depot, Progynova, Repestrogen, Repo-Estra, Reposo-E, Retestrin, Ronfase, Span-Est, Testaval, and Valergen, among others. Availability Oral estradiol valerate is used primarily in Europe, under the brand name Progynova. Although oral estradiol valerate was previously available in the United States, it is no longer available in the country except in combination with dienogest as a combined oral contraceptive (under the brand name Natazia). Estradiol valerate by intramuscular injection is available under the brand name Delestrogen in the United States and Canada and under the brand name Progynon Depot in Europe and elsewhere in the world. ==Research==

SH-834 was a combination of 90 mg estradiol valerate and 300 mg gestonorone caproate for weekly intramuscular injection that was developed by Schering in the 1970s. It was investigated clinically as a treatment for breast cancer and was found to be effective, but was never marketed. == See also ==