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Estradiol cypionate

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Estradiol cypionate
Clinical data
Pronunciation/ˌɛstrəˈdl sɪˈpnt/
ES-trə-DY-ohl sih-PY-oh-nate[1]
Trade namesDepo-Estradiol, Depofemin, Estradep, many others
Other namesEC; E2C; Estradiol cipionate; Estradiol cyclopentylpropionate; ECP; Estradiol 17β-cyclopentylpropionate; Estradiol 17β-cyclopentanepropionate
Routes of
administration
Intramuscular injection, subcutaneous injection[2]
Drug classEstrogen; Estrogen ester
ATC code
Legal status
Legal status
  • US: WARNING[3]
  • In general: ℞ (Prescription only)
Pharmacokinetic data
BioavailabilityIM: High[4]
Protein bindingEstradiol: ~98% (to albumin and SHBGTooltip sex hormone-binding globulin)[5][6]
MetabolismCleavage via esterases in the liver, blood, and tissues[7][8]
MetabolitesEstradiol, cypionic acid, and metabolites of estradiol[7][8]
Elimination half-lifeIM (aqueous suspension): 8–10 days[9][10]
Duration of actionIM (oil): 5 mg ≈ 11–14 days[11]
IM (aqueous suspension): 5 mg ≈ 14–24 days[9][12][13]
ExcretionUrine
Identifiers
  • [(8R,9S,13S,14S,17S)-3-hydroxy-13-methyl-6,7,8,9,11,12,14,15,16,17-decahydrocyclopenta[a]phenanthren-17-yl] 3-cyclopentylpropanoate
CAS Number
PubChem CID
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard100.005.672 Edit this at Wikidata
Chemical and physical data
FormulaC26H36O3
Molar mass396.571 g·mol−1
3D model (JSmol)
Melting point151 to 152 °C (304 to 306 °F)
  • C[C@]12CC[C@H]3[C@H]([C@@H]1CC[C@@H]2OC(=O)CCC4CCCC4)CCC5=C3C=CC(=C5)O
  • InChI=1S/C26H36O3/c1-26-15-14-21-20-10-8-19(27)16-18(20)7-9-22(21)23(26)11-12-24(26)29-25(28)13-6-17-4-2-3-5-17/h8,10,16-17,21-24,27H,2-7,9,11-15H2,1H3/t21-,22-,23+,24+,26+/m1/s1
  • Key:UOACKFBJUYNSLK-XRKIENNPSA-N

Estradiol cypionate (EC), 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 trans women, and in hormonal birth control for women.[14][8][15][16] It is given by injection into muscle once every 1 to 4 weeks.[14][17]

Side effects of estradiol cypionate include breast tenderness, breast enlargement, nausea, headache, and fluid retention.[14][8] Estradiol cypionate is an estrogen and hence is an agonist of the estrogen receptor, the biological target of estrogens like estradiol.[8][7] Estradiol cypionate is an estrogen ester and a long-lasting prodrug of estradiol in the body.[14][8][7] Because of this, it is considered to be a natural and bioidentical form of estrogen.[7][18][12]

Estradiol cypionate was first described as well as introduced for medical use in 1952.[19][20] Along with estradiol valerate, it is one of the most commonly used esters of estradiol.[21] Estradiol cypionate has mostly been used in the United States, but is also marketed in a few other countries.[22][23][24] The medication is not available in Europe.[25] It is not currently available as a generic medication in the United States.[26]

Medical uses

The medical uses of estradiol cypionate are the same as those of estradiol and other estrogens. Examples of indications for the drug include hormone therapy and hormonal contraception. In regard to the latter, estradiol cypionate has been used in combination with medroxyprogesterone acetate as a combined injectable contraceptive.[15][16][27] Along with estradiol valerate, estradiol undecylate, and estradiol benzoate, estradiol cypionate is used as a form of high-dose estrogen therapy in feminizing hormone therapy for transgender women.[28][17][29][30] The medication has been used to induce puberty in girls with delayed puberty due to hypogonadism.[31][25]

Estradiol cypionate is usually used at a dosage of 1 to 5 mg by intramuscular injection every 3 to 4 weeks in the treatment of menopausal symptoms such as hot flashes and vaginal atrophy, at a dosage of 1.5 to 2 mg by intramuscular injection once a month in the treatment of female hypoestrogenism due to hypogonadism, and at a dosage of 2 to 10 mg by intramuscular injection once every 1 or 2 weeks for hormone therapy in transgender women.[14][17][29][28][32] The doses used to induce puberty in girls are 0.2 to 2.5 mg per month, gradually increased over a period of 4 years.[31][25]

Estrogen dosages for menopausal hormone therapy
Route/form Estrogen Low Standard High
Oral Estradiol 0.5–1 mg/day 1–2 mg/day 2–4 mg/day
Estradiol valerate 0.5–1 mg/day 1–2 mg/day 2–4 mg/day
Estradiol acetate 0.45–0.9 mg/day 0.9–1.8 mg/day 1.8–3.6 mg/day
Conjugated estrogens 0.3–0.45 mg/day 0.625 mg/day 0.9–1.25 mg/day
Esterified estrogens 0.3–0.45 mg/day 0.625 mg/day 0.9–1.25 mg/day
Estropipate 0.75 mg/day 1.5 mg/day 3 mg/day
Estriol 1–2 mg/day 2–4 mg/day 4–8 mg/day
Ethinylestradiola 2.5–10 μg/day 5–20 μg/day
Nasal spray Estradiol 150 μg/day 300 μg/day 600 μg/day
Transdermal patch Estradiol 25 μg/dayb 50 μg/dayb 100 μg/dayb
Transdermal gel Estradiol 0.5 mg/day 1–1.5 mg/day 2–3 mg/day
Vaginal Estradiol 25 μg/day
Estriol 30 μg/day 0.5 mg 2x/week 0.5 mg/day
IMTooltip Intramuscular or SC injection Estradiol valerate 4 mg 1x/4 weeks
Estradiol cypionate 1 mg 1x/3–4 weeks 3 mg 1x/3–4 weeks 5 mg 1x/3–4 weeks
Estradiol benzoate 0.5 mg 1x/week 1 mg 1x/week 1.5 mg 1x/week
SC implant Estradiol 25 mg 1x/6 months 50 mg 1x/6 months 100 mg 1x/6 months
Footnotes: a = No longer used or recommended, due to health concerns. b = As a single patch applied once or twice per week (worn for 3–4 days or 7 days), depending on the formulation. Note: Dosages are not necessarily equivalent. Sources: See template.

Available forms

Estradiol cypionate is and has been available as an oil solution for intramuscular injection provided in vials and ampoules at concentrations of 1, 3, and 5 mg/mL (and containing 5, 10, 15, 25, or 50 mg estradiol cypionate total).[26][33][34] The 1 and 3 mg/mL concentrations (containing 5 and 15 mg estradiol cypionate total) have been discontinued in the United States, but the 5 mg/mL concentration (containing 25 mg estradiol cypionate total) remains available.[26][35] Aside from estradiol cypionate, the only other injectable estrogen formulations that remain available in the United States are estradiol valerate (10 mg/mL, 20 mg/mL, and 40 mg/mL in oil) and conjugated estrogens (25 mg/vial in solution).[26]

In addition to single-drug formulations, estradiol cypionate has been marketed in combination with medroxyprogesterone acetate as a microcrystalline aqueous suspension (brand name Lunelle) and in combination with testosterone cypionate as an oil solution (brand name Depo-Testadiol).[26]

Available forms of estradiol[a]
Route Ingredient Form Dose[b] Brand names[c]
Oral Estradiol Tablet 0.1, 0.2, 0.5, 1, 2, 4 mg Estrace, Ovocyclin
Estradiol valerate Tablet 0.5, 1, 2, 4 mg Progynova
Transdermal Estradiol Patch 14, 25, 37.5, 50, 60, 75, 100 µg/d Climara, Vivelle
Gel pump 0.06% (0.52, 0.75 mg/pump) Elestrin, EstroGel
Gel packet 0.1% (0.25, 0.5, 1.0 mg/pk.) DiviGel, Sandrena
Emulsion 0.25% (25 µg/pouch) Estrasorb
Spray 1.53 mg/spray Evamist, Lenzetto
Vaginal Estradiol Tablet 10, 25 µg Vagifem
Cream 0.01% (0.1 mg/gram) Estrace
Insert 4, 10 µg Imvexxy
Ring 2 mg/ring (7.5 µg/d, 3 mon.) Estring
Estradiol acetate Ring 50, 100 µg/d, 3 months Femring
Injection[d] Estradiol Microspheres 1 mg/mL Juvenum E
Estradiol benzoate Oil solution 0.167, 0.2, 0.333, 1, 1.67, 2, 5, 10, 20, 25 mg/mL Progynon-B
Estradiol cypionate Oil solution 1, 3, 5 mg/mL Depo-Estradiol
Estradiol valerate Oil solution 5, 10, 20, 40 mg/mL Progynon Depot
Implant Estradiol Pellet 20, 25, 50, 100 mg, 6 mon. Estradiol Implants
Notes and sources:
  1. ^ This table includes primarily products available as a single-ingredient estradiol preparation—thus excluding compounds with progestogens or other ingredients included. The table furthermore does not include compounded drugs—only commercially produced products. Availability of each product varies by country.
  2. ^ Doses are given per unit (ex: per tablet, per mL).
  3. ^ Other brand names may be manufactured or previously manufactured.
  4. ^ By intramuscular or subcutaneous injection.
Sources: [36][37][38][39][40][41][42][43][44][45][46][47][48][49]
5-mL vials of Depo-Estradiol (5 mg/mL estradiol cypionate in cottonseed oil solution for use by intramuscular injection) in the United States.[14]

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.[50][51][52][53]

Side effects

The side effects of estradiol cypionate are the same as those of estradiol. Examples of such side effects include breast tenderness and enlargement, nausea, vomiting, bloating, edema, headache, migraine, and melasma.[54][55] High-dose estrogen therapy with estradiol cypionate injections may also cause an increased risk of thromboembolism, changes in blood lipid profile, increased insulin resistance, and increased levels of prolactin.[55]

Overdose

Symptoms of estrogen overdosage may include nausea, vomiting, bloating, increased weight, water retention, breast tenderness, vaginal discharge, heavy legs, and leg cramps.[50] These side effects can be diminished by reducing the estrogen dosage.[50]

Interactions

Inhibitors and inducers of cytochrome P450 may influence the metabolism of estradiol and by extension circulating estradiol levels.[56]

Pharmacology

Estradiol, the active form of estradiol cypionate.

Pharmacodynamics

Estradiol cypionate is an estradiol ester, or a prodrug of estradiol.[8][7] As such, it is an estrogen, or an agonist of the estrogen receptors.[8][7] The affinity of estradiol valerate for the estrogen receptor has been reported to be 50 times less than that of estradiol,[4] and estradiol valerate and estradiol cypionate have been found to possess similar affinity for the estrogen receptor.[57] Both estradiol cypionate and estradiol valerate are rapidly cleaved into estradiol in the body,[8][58] and estradiol valerate has been found to be unable to reach target tissues in any concentration of significance.[4] As such, estradiol valerate is regarded as essentially inactive in terms of estrogenic effect itself, acting solely as a prodrug to estradiol,[4] and estradiol cypionate is described as a prodrug of estradiol similarly.[7] Estradiol cypionate is of about 46% higher molecular weight than estradiol due to the presence of its C17β cypionate ester, and contains about 69% of the amount of estradiol by weight.[59][22][25] Because estradiol cypionate is a prodrug of estradiol, it is considered to be a natural and bioidentical form of estrogen.[7][18][12]

Affinities and estrogenic potencies of estrogen esters and ethers at the estrogen receptors
Estrogen Other names RBATooltip Relative binding affinity (%)a REP (%)b
ER ERα ERβ
Estradiol E2 100 100 100
Estradiol 3-sulfate E2S; E2-3S ? 0.02 0.04
Estradiol 3-glucuronide E2-3G ? 0.02 0.09
Estradiol 17β-glucuronide E2-17G ? 0.002 0.0002
Estradiol benzoate EB; Estradiol 3-benzoate 10 1.1 0.52
Estradiol 17β-acetate E2-17A 31–45 24 ?
Estradiol diacetate EDA; Estradiol 3,17β-diacetate ? 0.79 ?
Estradiol propionate EP; Estradiol 17β-propionate 19–26 2.6 ?
Estradiol valerate EV; Estradiol 17β-valerate 2–11 0.04–21 ?
Estradiol cypionate EC; Estradiol 17β-cypionate ?c 4.0 ?
Estradiol palmitate Estradiol 17β-palmitate 0 ? ?
Estradiol stearate Estradiol 17β-stearate 0 ? ?
Estrone E1; 17-Ketoestradiol 11 5.3–38 14
Estrone sulfate E1S; Estrone 3-sulfate 2 0.004 0.002
Estrone glucuronide E1G; Estrone 3-glucuronide ? <0.001 0.0006
Ethinylestradiol EE; 17α-Ethynylestradiol 100 17–150 129
Mestranol EE 3-methyl ether 1 1.3–8.2 0.16
Quinestrol EE 3-cyclopentyl ether ? 0.37 ?
Footnotes: a = Relative binding affinities (RBAs) were determined via in-vitro displacement of labeled estradiol from estrogen receptors (ERs) generally of rodent uterine cytosol. Estrogen esters are variably hydrolyzed into estrogens in these systems (shorter ester chain length -> greater rate of hydrolysis) and the ER RBAs of the esters decrease strongly when hydrolysis is prevented. b = Relative estrogenic potencies (REPs) were calculated from half-maximal effective concentrations (EC50) that were determined via in-vitro β‐galactosidase (β-gal) and green fluorescent protein (GFP) production assays in yeast expressing human ERα and human ERβ. Both mammalian cells and yeast have the capacity to hydrolyze estrogen esters. c = The affinities of estradiol cypionate for the ERs are similar to those of estradiol valerate and estradiol benzoate (figure). Sources: See template page.
Potencies and durations of natural estrogens by intramuscular injection
Estrogen Form Dose (mg) Duration by dose (mg)
EPD CICD
Estradiol Aq. soln. ? <1 d
Oil soln. 40–60 1–2 ≈ 1–2 d
Aq. susp. ? 3.5 0.5–2 ≈ 2–7 d; 3.5 ≈ >5 d
Microsph. ? 1 ≈ 30 d
Estradiol benzoate Oil soln. 25–35 1.66 ≈ 2–3 d; 5 ≈ 3–6 d
Aq. susp. 20 10 ≈ 16–21 d
Emulsion ? 10 ≈ 14–21 d
Estradiol dipropionate Oil soln. 25–30 5 ≈ 5–8 d
Estradiol valerate Oil soln. 20–30 5 5 ≈ 7–8 d; 10 ≈ 10–14 d;
40 ≈ 14–21 d; 100 ≈ 21–28 d
Estradiol benz. butyrate Oil soln. ? 10 10 ≈ 21 d
Estradiol cypionate Oil soln. 20–30 5 ≈ 11–14 d
Aq. susp. ? 5 5 ≈ 14–24 d
Estradiol enanthate Oil soln. ? 5–10 10 ≈ 20–30 d
Estradiol dienanthate Oil soln. ? 7.5 ≈ >40 d
Estradiol undecylate Oil soln. ? 10–20 ≈ 40–60 d;
25–50 ≈ 60–120 d
Polyestradiol phosphate Aq. soln. 40–60 40 ≈ 30 d; 80 ≈ 60 d;
160 ≈ 120 d
Estrone Oil soln. ? 1–2 ≈ 2–3 d
Aq. susp. ? 0.1–2 ≈ 2–7 d
Estriol Oil soln. ? 1–2 ≈ 1–4 d
Polyestriol phosphate Aq. soln. ? 50 ≈ 30 d; 80 ≈ 60 d
Notes and sources
Notes: All aqueous suspensions are of microcrystalline particle size. Estradiol production during the menstrual cycle is 30–640 µg/d (6.4–8.6 mg total per month or cycle). The vaginal epithelium maturation dosage of estradiol benzoate or estradiol valerate has been reported as 5 to 7 mg/week. An effective ovulation-inhibiting dose of estradiol undecylate is 20–30 mg/month. Sources: See template.

Effects on liver protein synthesis

A study compared the combination of 5 mg estradiol cypionate and 25 mg medroxyprogesterone acetate as a combined injectable contraceptive (which has been associated with peak estradiol levels of around 300 pg/mL) with an ethinylestradiol-containing combined birth control pill and found that whereas the birth control pill produced significant changes in coagulation parameters, there were no significant prothrombotic effects of the combined injectable contraceptive on levels of fibrinogen, factors VII and X, plasminogen, or the activated prothrombin time.[60] As such, it appears that similarly to depot medroxyprogesterone acetate, combined injectable contraceptives with 5 mg estradiol cypionate and 25 mg medroxyprogesterone acetate have less or no procoagulant effect relative to combined birth control pills.[60]

Pharmacokinetics

Intramuscular injection

In contrast to oral administration, which is associated with very low bioavailability (<10%), the bioavailability of both estradiol and estradiol esters like estradiol valerate is complete (i.e., 100%) via intramuscular injection.[4][8] In addition, estradiol esters like estradiol cypionate and estradiol valerate when given as an injection of oil solution or microcrystalline aqueous suspension have a relatively long duration due to the formation of an intramuscular depot from which they are slowly released and absorbed.[4][61][62] Upon intramuscular injection of estradiol cypionate 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.[8] In addition, a secondary depot may be formed in adipose tissue.[8] The slow release of estradiol cypionate from the tissue depot is caused by the high lipophilicity of the estradiol ester, which in turn is due to its long fatty acid cypionic acid ester moiety.[4] Estradiol cypionate is formulated for use alone and in combination with testosterone cypionate as an oil solution, and for use in combination with medroxyprogesterone acetate as a microcrystalline aqueous suspension.[26][33][34][35] Aqueous suspensions of steroid esters generally have longer durations by intramuscular injection than oil solutions.[62]

A single intramuscular injection of 5 mg estradiol cypionate has been found to result in peak circulating concentrations of 338 pg/mL estradiol and 145 pg/mL estrone, which occurred at about 4 and 5 days post-injection, respectively (see right table).[11] Compared to two other commonly used estradiol esters (which were also assessed in the study), estradiol cypionate had the longest duration, at approximately 11 days, whereas estradiol benzoate and estradiol valerate were found to last for 4 to 5 days and 7 to 8 days, respectively.[11] This is because estradiol cypionate has a more extensive fatty acid chain and in relation to this is comparatively more lipophilic.[8] For a given estradiol ester, the longer or more extensive the fatty acid chain is, the more lipophilic, longer-lasting, and more uniform/plateau-like the resultant levels of estradiol are as well as the lower the peak/maximal levels are (and hence less spike-like).[8]

Estradiol cypionate/medroxyprogesterone acetate (brand names Lunelle, Cyclofem) is a combined injectable contraceptive containing 5 mg estradiol cypionate and 25 mg medroxyprogesterone acetate in microcrystalline aqueous suspension for once-monthly intramuscular administration.[12][13] With this formulations, estradiol levels peak 2 to 3 days post-injection with average maximal circulating levels of about 250 pg/mL.[9][12][13] The elimination half-life of estradiol with these formulations is 8.4 to 10.1 days, and circulating estradiol levels return to a baseline of about 50 pg/mL approximately 14 to 24 days post-injection.[9][12][13][10]

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.[2] 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.[2]

Chemistry

Estradiol cypionate is a synthetic estrane steroid and the C17β cyclopentylpropionate (cypionate) fatty acid ester of estradiol.[59][22] It is also known as estra-1,3,5(10)-triene-3,17β-diol 17β-cyclopentylpropionate.[59][22] 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.[69]

Structural properties of selected estradiol esters
Estrogen Structure Ester(s) Relative
mol. weight
Relative
E2 contentb
log Pc
Position(s) Moiet(ies) Type Lengtha
Estradiol
1.00 1.00 4.0
Estradiol acetate
C3 Ethanoic acid Straight-chain fatty acid 2 1.15 0.87 4.2
Estradiol benzoate
C3 Benzoic acid Aromatic fatty acid – (~4–5) 1.38 0.72 4.7
Estradiol dipropionate
C3, C17β Propanoic acid (×2) Straight-chain fatty acid 3 (×2) 1.41 0.71 4.9
Estradiol valerate
C17β Pentanoic acid Straight-chain fatty acid 5 1.31 0.76 5.6–6.3
Estradiol benzoate butyrate
C3, C17β Benzoic acid, butyric acid Mixed fatty acid – (~6, 2) 1.64 0.61 6.3
Estradiol cypionate
C17β Cyclopentylpropanoic acid Cyclic fatty acid – (~6) 1.46 0.69 6.9
Estradiol enanthate
C17β Heptanoic acid Straight-chain fatty acid 7 1.41 0.71 6.7–7.3
Estradiol dienanthate
C3, C17β Heptanoic acid (×2) Straight-chain fatty acid 7 (×2) 1.82 0.55 8.1–10.4
Estradiol undecylate
C17β Undecanoic acid Straight-chain fatty acid 11 1.62 0.62 9.2–9.8
Estradiol stearate
C17β Octadecanoic acid Straight-chain fatty acid 18 1.98 0.51 12.2–12.4
Estradiol distearate
C3, C17β Octadecanoic acid (×2) Straight-chain fatty acid 18 (×2) 2.96 0.34 20.2
Estradiol sulfate
C3 Sulfuric acid Water-soluble conjugate 1.29 0.77 0.3–3.8
Estradiol glucuronide
C17β Glucuronic acid Water-soluble conjugate 1.65 0.61 2.1–2.7
Estramustine phosphated
C3, C17β Normustine, phosphoric acid Water-soluble conjugate 1.91 0.52 2.9–5.0
Polyestradiol phosphatee
C3–C17β Phosphoric acid Water-soluble conjugate 1.23f 0.81f 2.9g
Footnotes: a = Length of ester in carbon atoms for straight-chain fatty acids or approximate length of ester in carbon atoms for aromatic or cyclic fatty acids. b = Relative estradiol content by weight (i.e., relative estrogenic exposure). c = Experimental or predicted octanol/water partition coefficient (i.e., lipophilicity/hydrophobicity). Retrieved from PubChem, ChemSpider, and DrugBank. d = Also known as estradiol normustine phosphate. e = Polymer of estradiol phosphate (~13 repeat units). f = Relative molecular weight or estradiol content per repeat unit. g = log P of repeat unit (i.e., estradiol phosphate). Sources: See individual articles.

History

Estradiol cypionate was patented by Upjohn in 1952, with a priority date of 1951.[33] It was first introduced for medical use by Upjohn in 1952 under the brand name Depo-Estradiol in the United States.[19][20][70] Subsequently, it was also marketed in other countries such as European countries and Japan.[33][20][22] The first clinical reports of estradiol cypionate were published in 1952 and thereafter.[71][72][73][74][68] 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.[72][73][75] Along with estradiol valerate (1954)[20][76] and estradiol benzoate (1933),[77][78][79] estradiol cypionate has become one of the most commonly used esters of estradiol.[21]

When estradiol cypionate was to be combined with medroxyprogesterone acetate as a once-a-month injectable contraceptive, there was a problem in that estradiol cypionate was prepared as an oil solution while medroxyprogesterone acetate was used as a microcrystalline aqueous suspension.[80] This issue was resolved by switching to a microcrystalline aqueous suspension in the case of estradiol cypionate, allowing it to be combined with medroxyprogesterone acetate in a single suspension.[80] As a result, single-drug preparations of estradiol cypionate are oil solutions, while the combination of estradiol cypionate and medroxyprogesterone acetate are microcrystalline aqueous suspensions.[80]

Society and culture

Generic names

Estradiol cypionate is the generic name of the drug and its INNTooltip International Nonproprietary Name and USANTooltip United States Adopted Name.[59][22][23] It is also known as estradiol cyclopentylpropionate (ECP).[72][73]

Brand names

Estradiol cypionate has been marketed under the brand names Cicloestradiolo, D-Est, depGynogen, Depo-Estradiol, Depoestra, Depofemin, Depogen, Dura-Estrin, E-Cypionate, E-Ionate, Estradep, Estro-Cyp, Estrofem, Estroject, Estromed-PA, Estronol, Femovirin, Neoginon Depositum, Oestradiol-Retard, Pertradiol, Spendepiol, and T-E Cypionate, among others.[59][22][20][23]

Availability

Estradiol cypionate is available in the United States.[26][23][25] It was previously marketed in Spain and Italy, but was discontinued in these countries and is no longer available in Europe.[22][25] Estradiol cypionate has mostly been used in the United States, similarly to testosterone cypionate, with both of these medications having been developed by Upjohn, an American pharmaceutical company.[22][24] Besides the United States, estradiol cypionate has been marketed in France, Germany, Italy, Spain, and Japan, among other countries.[33][20][22] Estradiol cypionate is not available in Canada, although it is marketed in several veterinary formulations in this country.[81]

Estradiol cypionate is available in Taiwan in combination with testosterone cypionate.[23] 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.[82][83][84][16][85][86][87] Estradiol cypionate/testosterone cypionate and estradiol cypionate/medroxyprogesterone acetate were both formerly marketed in the United States, but have been discontinued in this country.[26]

See also

References

  1. ^ "Estradiol: Uses, Dosage & Side Effects". Drugs.com. Retrieved 21 April 2023.
  2. ^ a b c d e f Sierra-Ramírez JA, Lara-Ricalde R, Lujan M, Velázquez-Ramírez N, Godínez-Victoria M, Hernádez-Munguía IA, Padilla A, Garza-Flores J (2011). "Comparative pharmacokinetics and pharmacodynamics after subcutaneous and intramuscular administration of medroxyprogesterone acetate (25 mg) and estradiol cypionate (5 mg)". Contraception. 84 (6): 565–70. doi:10.1016/j.contraception.2011.03.014. PMID 22078184.
  3. ^ "FDA-sourced list of all drugs with black box warnings (Use Download Full Results and View Query links.)". nctr-crs.fda.gov. FDA. Retrieved 22 Oct 2023.
  4. ^ a b c d e f g Düsterberg B, Nishino Y (December 1982). "Pharmacokinetic and pharmacological features of oestradiol valerate". Maturitas. 4 (4): 315–24. doi:10.1016/0378-5122(82)90064-0. PMID 7169965.
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