Estradiol .75 mg/1.25g Gel, Metered, 50 g
Other active recalls for Estradiol (different manufacturers) — 4 · tap to view
🆔 Identity & classification
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🏷️ RxNorm drug class
This medicine belongs to the Radioactive Diagnostic Agent class.
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🏭 Manufacturer & labeler
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🩺 Clinical
- Estradiol is a form of estrogen — the main female sex hormone. When estrogen levels fall after menopause (or due to other conditions like ovarian failure), you can get symptoms lik...
- What exactly is estradiol and why has my doctor prescribed it?
- Apply the patch to a clean, dry area of skin — usually the lower abdomen. Never put it on your breasts. Press it firmly in place and leave it on for the full wear period — once a w...
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Patient education
Supplement & herbal interactions
Some supplements/herbs that may interact with Estradiol — tap one for details:
Estradiol may be associated with lower levels of 5 nutrients — worth a chat with your pharmacist, not a cause for alarm.
Where does this data come from?
Ask a licensed pharmacist directly — free, answered by our team.
🧪 Inactive Ingredients / Excipients
Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.
💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.
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UNII 3K9958V90M
A liquid solvent derived from fermentation or chemical synthesis. In medicines, alcohol dissolves active ingredients, helps preserve the product, and improves how the body absorbs certain drugs.
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UNII HHT01ZNK31
Carbomer Homopolymer Type B is a synthetic polymer made from acrylic acid. It absorbs water and forms a gel, so it's used in medicines as a thickener, suspending agent, and to help create a smooth texture in creams, gels, and lotions.
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UNII 9O3K93S3TK
Trolamine is an alkaline compound used as a pH buffer and emulsifier in medicines. It helps neutralize acids, stabilize formulations, and enable mixing of oil and water-based ingredients.
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UNII 059QF0KO0R
Water is a liquid solvent that dissolves and mixes ingredients together in liquid medicines, syrups, and injections. It helps distribute the active drug evenly throughout the product.
4 inactive ingredients listed in the exact product block matched to this NDC.
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ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.Inactive ingredient FAQ
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💲 Pricing
A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.
| Price system | Per g | Per package |
|---|---|---|
| Retail pharmacies payNADAC · weekly | $3.414 | $170.72 / 50 g |
| Medicaid paysCMS SDUD · 12 mo | $3.30 | $165.20 / 50 g |
| Medicare drug plans payPart D · Q2 2026 | $3.04 | $152.14 / 50 g |
Where does this data come from?
🔁 Therapeutic equivalents
| Product | Labeler | Pack | NADAC/unit | TE | Status | Price vs. this |
|---|---|---|---|---|---|---|
| Estradiol .75 mg/1.25gthis 70954-0646-10 | ANI | 50 g | $3.414 | AB | Availability likely | — |
| Estradiol .75 mg/1.25g 73473-0308-50 | Solaris | 1 bottle | $3.414 | AB | Availability likely | — |
| Elestrin .52 mg/.87g 00037-4801-70 | Viatris | 2 bottles | $3.610 | — | Availability likely | +6% |
| EstroGel .75 mg/1.25g 17139-0617-40 | ASCEND | 50 g | — | AB | FDA listed | — |
| Estradiol .75 mg/1.25g 21922-0015-40 | Encube | 1 bottle | — | AB | FDA listed | — |
Where does this data come from?
⏳ Availability & generic status
This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.
Where does this data come from?
🗺️ Medicaid utilization & spend
📊 Medicare Part D spend CMS · PART D · 2026 (Q1)
📦 Packaging — all sizes for this product
| Package NDC | Description | Marketing start | Status |
|---|---|---|---|
| 70954-0646-10 You're viewing this | 50 g in 1 BOTTLE, PUMP (70954-646-10) | 2024-10-23 | Active |
📄 Full prescribing information FDA SPL
🚨 Boxed Warning ▾
BOXED WARNING WARNING: ENDOMETRIAL CANCER, CARDIOVASCULAR DISORDERS, PROBABLE DEMENTIA and BREAST CANCER Estrogen-Alone Therapy Endometrial Cancer There is an increased risk of endometrial cancer in a woman with a uterus who uses unopposed estrogens. Adding a progestogen to estrogen therapy has been shown to reduce the risk of endometrial hyperplasia, which may be a precursor to endometrial cancer. Perform adequate diagnostic measures, including directed or random endometrial sampling when indicated, to rule out malignancy in postmenopausal women with undiagnosed, persistent, or recurring abnormal genital bleeding [see Warnings and Precautions (5.2)].
Cardiovascular Disorders and Probable Dementia The Women's Health Initiative (WHI) estrogen-alone substudy reported increased risks of stroke and deep vein thrombosis (DVT) in postmenopausal women (50 to 79 years of age) during 7.1 years of treatment with daily oral conjugated estrogens (CE) [0.625 mg]-alone, relative to placebo [see Warnings and Precautions (5.1), and Clinical Studies (14.3)]. The WHI Memory Study (WHIMS) estrogen-alone ancillary study of WHI reported an increased risk of developing probable dementia in postmenopausal women 65 years of age or older during 5.2 years of treatment with daily CE (0.625 mg)-alone, relative to placebo.
It is unknown whether this finding applies to younger postmenopausal women [see Warnings and Precautions (5.3), Use in Specific Populations (8.5), and Clinical Studies (14.4)] . Do not use estrogen-alone therapy for the prevention of cardiovascular disease or dementia [see Warnings and Precautions (5.1, 5.3), and Clinical Studies (14.3, 14.4). Only daily oral 0.625 mg CE was studied in the estrogen-alone substudy of the WHI.
Therefore, the relevance of the WHI findings regarding adverse cardiovascular events and dementia to lower CE doses, other routes of administration, or other estrogen-alone products is not known. Without such data, it is not possible to definitively exclude these risks or determine the extent of these risks for other products. Discuss with your patient the benefits and risks of estrogen-alone therapy, taking into account her individual risk profile.
Prescribe estrogens with or without progestogens at the lowest effective doses and for the shortest duration consistent with treatment goals and risks for the individual woman. Estrogen Plus Progestin Therapy Cardiovascular Disorders and Probable Dementia The WHI estrogen plus progestin substudy reported increased risks of pulmonary embolism (PE), DVT, stroke and myocardial infarction (MI) in postmenopausal women (50 to 79 years of age) during 5.6 years of treatment with daily oral CE (0.625 mg) combined with medroxyprogesterone acetate (MPA) [2.5 mg], relative to placebo [see Warnings and Precautions (5.1), and Clinical Studies (14.3)].
The WHIMS estrogen plus progestin ancillary study of WHI reported an increased risk of developing probable dementia in postmenopausal women 65 years of age or older during 4 years of treatment with daily CE (0.625 mg) combined with MPA (2.5 mg), relative to placebo. It is unknown whether this finding applies to younger postmenopausal women [see Warnings and Precautions (5.3), Use in Specific Populations (8.5), and Clinical Studies (14.4)]. Do not use estrogen plus progestogen therapy for the prevention of cardiovascular disease or dementia [see Warnings and Precautions (5.1, 5.3), and Clinical Studies (14.3, 14.4)] .
Breast Cancer The WHI estrogen plus progestin substudy also demonstrated an increased risk of invasive breast cancer [see Warnings and Precautions (5.2), and Clinical Studies (14.4)] . Only daily oral 0.625 mg CE and 2.5 mg MPA were studied in the estrogen plus progestin substudy of the WHI. Therefore, the relevance of the WHI findings regarding adverse cardiovascular events, dementia and breast cancer to lower CE plus other MPA doses, other routes of administration, or other estrogen plus progestogen products is not known.…
🎯 Indications and Usage ▾
1 INDICATIONS & USAGE Estradiol gel 0.06% is an estrogen indicated for: Treatment of moderate to severe vasomotor symptoms due to menopause (1.1) Treatment of moderate to severe symptoms of vulvar and vaginal atrophy due to menopause (1.2)
1.1Treatment of Moderate to Severe Vasomotor Symptoms due to Menopause .
1.2Treatment of Moderate to Severe Symptoms of Vulvar and Vaginal Atrophy due to Menopause Limitation of Use When prescribing solely for the treatment of moderate to severe symptoms of vulvar and vaginal atrophy due to menopause, first consider the use of topical vaginal products.
⏱️ Dosage and Administration ▾
2 DOSAGE & ADMINISTRATION Generally, when estrogen is prescribed for a postmenopausal woman with a uterus, consider addition of a progestogen to reduce the risk of endometrial cancer. Generally, a woman without a uterus does not need to use a progestogen in addition to her estrogen therapy. In some cases, however, hysterectomized women with a history of endometriosis may need a progestogen [see Warnings and Precautions (5.2, 5.14)] .
Use estrogen-alone, or in combination with a progestogen at the lowest effective dose and for the shortest duration consistent with treatment goals and risks for the individual woman. Reevaluate postmenopausal women periodically as clinically appropriate to determine if treatment is still necessary. Metered-dose pump: Daily administration of estradiol gel 0.06% 1.25 g per day (1 pump depression) to the arm (2.1, 2.2)
2.1Treatment of Moderate to Severe Vasomotor Symptoms due to Menopause Estradiol gel 0.06% 1.25 g per day is the single approved dose for the treatment of moderate to severe vasomotor symptoms due to menopause. The lowest effective dose of estradiol gel 0.06% for this indication has not been determined. Before using the canister for the first time, it must be primed.
Remove the large canister cover, and fully depress the pump 5 times. Discard the unused gel by thoroughly rinsing down the sink or placing it in the household trash. After priming, the pump is ready to use.
The recommended area of application is the arm. Apply a thin layer over the entire arm on the inside and outside from wrist to shoulder.
2.2Treatment of Moderate to Severe Symptoms of Vulvar and Vaginal Atrophy due to Menopause Estradiol gel 0.06% 1.25 g per day is the single approved dose for the treatment of moderate to severe symptoms of vulvar and vaginal atrophy due to menopause. The lowest effective dose of estradiol gel 0.06% for this indication has not been determined. When prescribing solely for the treatment of moderate to severe symptoms of vulvar and vaginal atrophy, first consider the use of topical vaginal products.
Before using the canister for the first time, it must be primed. Remove the large canister cover, and fully depress the pump 5 times. Discard the unused gel by thoroughly rinsing down the sink or placing it in the household trash.
After priming, the pump is ready to use. The recommended area of application is the arm. Apply a thin layer over the entire arm on the inside and outside from wrist to shoulder.
💊 Dosage Forms and Strengths ▾
3 DOSAGE FORMS & STRENGTHS Estradiol gel 0.06% is an estradiol transdermal gel. One pump depression delivers 1.25 g of gel that contains 0.75 mg estradiol. Gel: 1 pump depression of estradiol gel 0.06% delivers 1.25 g of gel containing 0.75 mg estradiol (3)
⛔ Contraindications ▾
4 CONTRAINDICATIONS Estradiol gel is contraindicated in women with any of the following conditions: Undiagnosed abnormal genital bleeding [see Warning and Precautions (5.2)]. Breast cancer or a history of breast cancer [see Warning and Precautions (5.2)]. Estrogen-dependent neoplasia [see Warning and Precautions (5.2)].
Active DVT, PE, or history of these conditions [see Warning and Precautions (5.1)]. Active arterial thromboembolic disease (for example, stroke or MI), or a history of these conditions [see Warning and Precautions (5.1)]. Known anaphylactic reaction, angioedema, or hypersensitivity to estradiol gel Hepatic impairment or disease Protein C, protein S, or antithrombin deficiency, or other known thrombophilic disorders Undiagnosed abnormal genital bleeding (4, 5.2) Breast cancer or a history of breast cancer (4, 5.2) Estrogen-dependent neoplasia (4, 5.2) Active DVT, PE, or history of these conditions (4, 5.1) Active arterial thromboembolic disease (for example, stroke or MI), or a history of these conditions (4, 5.1) Known anaphylactic reaction, angioedema, or hypersensitivity to estradiol gel (4) Hepatic impairment or disease (4, 5.10) Protein C, protein S, or antithrombin deficiency, or other known thrombophilic disorders (4)
⚠️ Warnings and Cautions ▾
5 WARNINGS AND PRECAUTIONS Estrogens increase the risk of gallbladder disease (5.4) Discontinue estrogen if severe hypercalcemia, loss of vision, severe hypertriglyceridemia or cholestatic jaundice occurs (5.5, 5.6, 5.9, 5.10) Monitor thyroid function in women on thyroid replacement therapy (5.11, 5.20)
5.1Cardiovascular Disorders Increased risks of stroke and DVT are reported with estrogen-alone therapy. Increased risks of PE, DVT, stroke and MI are reported with estrogen plus progestin therapy. Immediately discontinue estrogen with or without progestogen if any of these occur or are suspected.
Manage appropriately any risk factors for arterial vascular disease (for example, hypertension, diabetes mellitus, tobacco use, hypercholesterolemia, and obesity) and/or venous thromboembolism (VTE) (for example, personal history or family history of VTE, obesity, and systemic lupus erythematosus). Stroke The WHI estrogen-alone substudy reported a statistically significant increased risk of stroke in women 50 to 79 years of age receiving daily CE (0.625 mg)-alone compared to women in the same age group receiving placebo (45 versus 33 per 10,000 women-years, respectively).
The increase in risk was demonstrated in year 1 and persisted [see Clinical Studies (14.3)] . Immediately discontinue estrogen-alone therapy if a stroke occurs or is suspected. Subgroup analysis of women 50 to 59 years of age suggest no increased risk of stroke for those women receiving CE (0.625 mg)-alone versus those receiving placebo (18 versus 21 per 10,000 women-years).
1 The WHI estrogen plus progestin substudy reported a statistically significant increased risk of stroke in women 50 to 79 years of age receiving daily CE (0.625 mg) plus MPA (2.5 mg) compared to women in the same age group receiving placebo (33 versus 25 per 10,000 women-years) [see Clinical Studies (14.3)] . The increase in risk was demonstrated after the first year and persisted. 1 Immediately discontinue estrogen with or without progestogen therapy if a stroke occurs or is suspected.
Coronary Heart Disease The WHI estrogen-alone substudy reported no overall effect on coronary heart disease (CHD) events (defined as nonfatal MI, silent MI, or CHD death) in women receiving estrogen-alone compared to placebo 2 [see Clinical Studies (14.3)]. Subgroup analyses of women 50 to 59 years of age, who were less than 10 years since menopause, suggest a reduction (not statistically significant) of CHD events in those women receiving CE (0.625 mg)-alone compared to placebo) (8 versus 16 per 10,000 women-years).
1 The WHI estrogen plus progestin substudy reported an increased risk (not statistically significant) of CHD events in those women receiving daily CE (0.625 mg) plus MPA (2.5 mg) compared to women receiving placebo (41 versus 34 per 10,000 women-years). 1 An increase in relative risk was demonstrated in year 1, and a trend toward decreasing relative risk was reported in years 2 through 5 [see Clinical Studies (14.3)]. In postmenopausal women with documented heart disease (n = 2,763, average 66.7 years of age), in a controlled clinical trial of secondary prevention of cardiovascular disease (Heart and Estrogen/Progestin Replacement Study; HERS), treatment with daily CE (0.625 mg) plus MPA (2.5 mg) demonstrated no cardiovascular benefit.
During an average follow-up of 4.1 years, treatment with CE plus MPA did not reduce the overall rate of CHD events in postmenopausal women with established CHD. There were more CHD events in the CE plus MPA-treated group than in the placebo group in year 1, but not during the subsequent years. Two thousand, three hundred twenty-one (2,321) women from the original HERS trial agreed to participate in an open-label extension of the original HERS, HERS II.
Average follow-up in HERS II was an additional 2.7 years, for a total of 6.8 years overall. Rates of CHD events were comparable among women in the CE plus MPA group and the placebo group in HERS, HERS II, and overall. Ve…
🤒 Adverse Reactions ▾
6 ADVERSE REACTIONS The following serious adverse reactions are discussed elsewhere in the labeling: Cardiovascular Disorders [see Boxed Warning, and Warnings and Precautions (5.1)] Malignant Neoplasms [see Boxed Warning, and Warnings and Precautions (5.2)] The most common adverse reactions with estradiol gel (≥5 percent) are: headache, flatulence, and breast pain. (6.1) To report SUSPECTED ADVERSE REACTIONS, contact ANI Pharmaceuticals, Inc. at 1-855-204-1431 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch .
6.1Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. Estradiol gel was studied in 2 well-controlled, 12-week clinical trials. Incidence of adverse drug reactions ≥5 percent for 1.25 g estradiol gel 0.06% and placebo is given in Table 1.
TABLE 1 Incidence of Adverse Drug Reactions ≥5 Percent Occurrence in the Estradiol Gel Treatment Group for the Intent-to-Treat Safety Population in 2 Well-controlled Clinical Studies (Expressed as Percent of Treatment Group) Body System/ Adverse Drug Reactions Estradiol gel 0.06% 1.25 g /day (n=168) Placebo (n=73) BODY AS A WHOLE Headache 9.5
2.7DIGESTIVE SYSTEM Flatulence 5.4
4.1UROGENITAL SYSTEM Breast pain 10.7
8.2In 2 controlled clinical trials, application site reactions were reported by 0.6 percent of patients who received 1.25 g of estradiol gel. Other skin reactions, such as pruritus and rash, were also noted.
6.2Postmarketing Experience The following adverse reactions have been identified during post-approval use of estradiol gel. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Genitourinary system Endometrial cancer Breast Pain; tenderness; breast cancer Cardiovascular Deep vein thrombosis; myocardial ischemia; phlebitis Gastrointestinal Nausea; abdominal distension; diarrhea; stomach discomfort Skin Alopecia; rash; pruritus; application site: dryness, pain, discoloration, reaction, rash Eyes Retinal vein occlusion Central nervous system Headache; dizziness; insomnia; hypoesthesia; meningioma; aphasia; bradyphrenia; paresthesia Miscellaneous Drug ineffective; hot flush; arthralgia; night sweats; drug effect decreased; pain in extremity; fatigue; weight increased; pain; hypersensitivity; dyspnea; malignant mesenchymoma; angioedema; hepatitis acute; face edema; accidental exposure; myoclonus; gait disturbance; flushing
🔄 Drug Interactions ▾
7 DRUG INTERACTIONS In vitro and in vivo studies have shown that estrogens are metabolized partially by cytochrome P450 3A4 (CYP3A4). Therefore, inducers or inhibitors of CYP3A4 may affect estrogen drug metabolism. Inducers of CYP3A4, such as St.
John’s wort ( Hypericum perforatum ) preparations, phenobarbital, carbamazepine, and rifampin, may reduce plasma concentrations of estrogens, possibly resulting in a decrease in therapeutic effects and/or changes in the uterine bleeding profile. Inhibitors of CYP3A4 such as erythromycin, clarithromycin, ketoconazole, itraconazole, ritonavir, and grapefruit juice may increase plasma concentrations of estrogen and may result in adverse reactions. Inducers and/or inhibitors of CYP3A4 may affect estrogen drug metabolism and decrease or increase the estrogen plasma concentration.
(7.1)
👥 Use in Specific Populations ▾
8 USE IN SPECIFIC POPULATIONS
8.1Pregnancy Risk Summary Estradiol gel is not indicated for use in pregnancy . There are no data with the use of estradiol gel in pregnant women, however, epidemiologic studies and meta-analysis have not found an increased risk of genital or non-genital birth defects (including cardiac anomalities and limb-reduction defects) following exposure to combined hormonal contraceptives (estrogens and progestins) before conception or during early pregnancy. In the U.S. general population, the estimated background rate of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.
8.3Lactation Estrogens are present in human milk and can reduce milk production in breast-feeding women. This reduction can occur at any time but is less likely to occur once breast-feeding is well established. The development and health benefits of breastfeeding should be considered along with the mother’s clinical need for estradiol gel and any potential adverse effects on the breastfed child from estradiol gel or from the underlying maternal condition.
8.4Pediatric Use Estradiol gel is not indicated for use in pediatric patients. Clinical studies have not been conducted in the pediatric population.
8.5Geriatric Use There have not been sufficient numbers of geriatric women involved in clinical studies utilizing estradiol gel to determine whether those over 65 years of age differ from younger subjects in their response to estradiol gel. The Women’s Health Initiative Studies In the WHI estrogen-alone substudy (daily CE [0.625 mg]-alone versus placebo), there was a higher relative risk of stroke in women greater than 65 years of age [see Warnings and Precautions (5.1) and Clinical Studies (14.3)] . In the WHI estrogen plus progestin substudy (daily CE [0.625 mg] plus MPA [2.5 mg] versus placebo), there was a higher relative risk of nonfatal stroke and invasive breast cancer in women greater than 65 years of age [see Warnings and Precautions (5.1) and Clinical Studies (14.3)] .
The Women’s Health Initiative Memory Study In the WHIMS ancillary studies of postmenopausal women 65 to 79 years of age, there was an increased risk of developing probable dementia in women receiving estrogen-alone or estrogen plus progestin when compared to placebo [see Warnings and Precautions (5.3), and Clinical Studies (14.4)] . Since both ancillary studies were conducted in women 65 to 79 years of age, it is unknown whether these findings apply to younger postmenopausal women 8 [see Warnings and Precautions (5.3), and Clinical Studies (14.4)] .
🤰 Pregnancy ▾
8.1Pregnancy Risk Summary Estradiol gel is not indicated for use in pregnancy . There are no data with the use of estradiol gel in pregnant women, however, epidemiologic studies and meta-analysis have not found an increased risk of genital or non-genital birth defects (including cardiac anomalities and limb-reduction defects) following exposure to combined hormonal contraceptives (estrogens and progestins) before conception or during early pregnancy. In the U.S. general population, the estimated background rate of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.
🧒 Pediatric Use ▾
8.4Pediatric Use Estradiol gel is not indicated for use in pediatric patients. Clinical studies have not been conducted in the pediatric population.
🧓 Geriatric Use ▾
8.5Geriatric Use There have not been sufficient numbers of geriatric women involved in clinical studies utilizing estradiol gel to determine whether those over 65 years of age differ from younger subjects in their response to estradiol gel. The Women’s Health Initiative Studies In the WHI estrogen-alone substudy (daily CE [0.625 mg]-alone versus placebo), there was a higher relative risk of stroke in women greater than 65 years of age [see Warnings and Precautions (5.1) and Clinical Studies (14.3)] . In the WHI estrogen plus progestin substudy (daily CE [0.625 mg] plus MPA [2.5 mg] versus placebo), there was a higher relative risk of nonfatal stroke and invasive breast cancer in women greater than 65 years of age [see Warnings and Precautions (5.1) and Clinical Studies (14.3)] .
The Women’s Health Initiative Memory Study In the WHIMS ancillary studies of postmenopausal women 65 to 79 years of age, there was an increased risk of developing probable dementia in women receiving estrogen-alone or estrogen plus progestin when compared to placebo [see Warnings and Precautions (5.3), and Clinical Studies (14.4)] . Since both ancillary studies were conducted in women 65 to 79 years of age, it is unknown whether these findings apply to younger postmenopausal women 8 [see Warnings and Precautions (5.3), and Clinical Studies (14.4)] .
🆘 Overdosage ▾
10 OVERDOSAGE Overdosage of estrogen may cause nausea, vomiting, breast tenderness, abdominal pain, drowsiness and fatigue, and withdrawal bleeding may occur in women. Treatment of overdose consists of discontinuation of estradiol gel therapy with institution of appropriate symptomatic care.
🧬 Clinical Pharmacology ▾
12 CLINICAL PHARMACOLOGY
12.1Mechanism of Action Endogenous estrogens are largely responsible for the development and maintenance of the female reproductive system and secondary sexual characteristics. Although circulating estrogens exist in a dynamic equilibrium of metabolic interconversions, estradiol is the principal intracellular human estrogen and is substantially more potent than its metabolites, estrone and estriol, at the receptor level. The primary source of estrogen in normally cycling adult women is the ovarian follicle, which secretes 70 to 500 mcg of estradiol daily, depending on the phase of the menstrual cycle.
After menopause, most endogenous estrogen is produced by conversion of androstenedione, secreted by the adrenal cortex, to estrone in the peripheral tissues. Thus, estrone and the sulfate-conjugated form, estrone sulfate, are the most abundant circulating estrogens in postmenopausal women. Estrogens act through binding to nuclear receptors in estrogen-responsive tissues.
To date, 2 estrogen receptors have been identified. These vary in proportion from tissue to tissue. Circulating estrogens modulate the pituitary secretion of the gonadotropins, luteinizing hormone (LH) and FSH through a negative feedback mechanism.
Estrogens act to reduce the elevated levels of these hormones seen in postmenopausal women.
12.2Pharmacodynamics Generally, a serum estrogen concentration does not predict an individual woman’s therapeutic response to estradiol gel nor her risk for adverse outcomes. Likewise, exposure comparisons across different estrogen products to infer efficacy or safety for the individual woman may not be valid.
12.3Pharmacokinetics Absorption Estradiol is transported across intact skin and into the systemic circulation by a passive diffusion process. The rate of diffusion across the stratum corneum is the rate-limiting factor. When estradiol gel is applied to the skin, it dries in 2 to 5 minutes.
Estradiol gel 1.25 g (containing 0.75 mg of estradiol) was administered to 24 postmenopausal women once daily on the posterior surface of 1 arm from wrist to shoulder for 14 consecutive days. Mean maximal serum concentrations of estradiol and estrone on Day 14 were 46.4 pg/mL and 64.2 pg/mL, respectively. The time-averaged serum estradiol and estrone concentrations over the 24-hour dose interval after administration of 1.25 g estradiol gel on Day 14 are 28.3 pg/mL and 48.6 pg/mL, respectively.
Mean concentration-time profiles for unadjusted estradiol and estrone on Day 14 are shown in Figure 1. FIGURE 1 Mean Serum Concentration-time Profiles for Unadjusted Estradiol and Estrone After Multiple-dose Applications of 1.25 g Estradiol Gel 0.06% for 14 Days The serum concentrations of estradiol following 2.5 g estradiol gel applications (1.25 g on each arm from wrist to shoulder) appeared to reach steady state after the third daily application. Distribution The distribution of exogenous estrogens is similar to that of endogenous estrogens.
Estrogens are widely distributed in the body and are generally found in higher concentrations in the sex hormone target organs. Estrogens circulate in blood largely bound to SHBG and albumin. Metabolism Exogenous estrogens are metabolized in the same manner as endogenous estrogens.
Circulating estrogens exist in a dynamic equilibrium of metabolic interconversions. These transformations take place mainly in the liver. Estradiol is converted reversibly to estrone, and both can be converted to estriol, which is a major urinary metabolite.
Estrogens also undergo enterohepatic recirculation via sulfate and glucuronide conjugation in the liver, biliary secretion of conjugates into the intestine, and hydrolysis in the intestine followed by reabsorption. In postmenopausal women, a significant proportion of the circulating estrogens exist as sulfate conjugates, especially estrone sulfate, which serves as a circulating reservoir for the formation of more active estrogens. Although the clini…
🧬 Mechanism of Action ▾
12.1Mechanism of Action Endogenous estrogens are largely responsible for the development and maintenance of the female reproductive system and secondary sexual characteristics. Although circulating estrogens exist in a dynamic equilibrium of metabolic interconversions, estradiol is the principal intracellular human estrogen and is substantially more potent than its metabolites, estrone and estriol, at the receptor level. The primary source of estrogen in normally cycling adult women is the ovarian follicle, which secretes 70 to 500 mcg of estradiol daily, depending on the phase of the menstrual cycle.
After menopause, most endogenous estrogen is produced by conversion of androstenedione, secreted by the adrenal cortex, to estrone in the peripheral tissues. Thus, estrone and the sulfate-conjugated form, estrone sulfate, are the most abundant circulating estrogens in postmenopausal women. Estrogens act through binding to nuclear receptors in estrogen-responsive tissues.
To date, 2 estrogen receptors have been identified. These vary in proportion from tissue to tissue. Circulating estrogens modulate the pituitary secretion of the gonadotropins, luteinizing hormone (LH) and FSH through a negative feedback mechanism.
Estrogens act to reduce the elevated levels of these hormones seen in postmenopausal women.
📦 How Supplied / Storage and Handling ▾
16 HOW SUPPLIED/STORAGE AND HANDLING
16.1How Supplied Estradiol gel is a clear, colorless, hydroalcoholic gel containing 0.06 percent estradiol, supplied in a non-aerosol, metered-dose pump. The pump consists of an LDPE inner liner encased in rigid plastic with a resealable polypropylene cap. Estradiol gel is available in a 50-gram (1.75 oz) size. Each individually packaged 50-gram pump contains 50 grams of gel and can deliver 30 metered 1.25-g doses. NDC: 70954-646-10 50-gram pump
16.2Storage and Handling Keep this and all medication out of the reach of children. Store at 20° to 25°C (68° to 77°F); excursions permitted to 15° to 30°C (59° to 86°F) [See USP Controlled Room Temperature].
📋 Description ▾
11 DESCRIPTION Estradiol gel contains 0.06 percent estradiol in an absorptive hydroalcoholic gel base for topical application. It is a clear, colorless hydroalcoholic gel. One pump depression of estradiol gel delivers 1.25 g of gel containing 0.75 mg estradiol.
Estradiol is a white crystalline powder, chemically described as estra-1,3,5(10)-triene-3,17β-diol. It has an empirical formula of C 18 H 24 O 2 and molecular weight of 272.39. The structural formula is: The active component of the gel is estradiol.
The remaining components of the gel (purified water, alcohol (46%), triethanolamine and carbomer 974P) are pharmacologically inactive. structure
💬 Information for Patients ▾
17 PATIENT COUNSELING INFORMATION Advise women to read the FDA-approved patient labeling (Patient Information and Instructions for Use) Vaginal Bleeding Inform postmenopausal women to report any vaginal bleeding to their healthcare provider as soon as possible [see Warnings and Precautions (5.2)] . Possible Serious Adverse Reactions with Estrogen-Alone Therapy Inform postmenopausal women of the possible serious adverse reactions of estrogen-alone therapy including Cardiovascular Disorders, Malignant Neoplasms, and Probable Dementia [see Warnings and Precautions (5.1, 5.2, 5.3).
Possible Common Adverse Reactions with Estrogen-Alone Therapy Inform postmenopausal women of possible less serious but common adverse reactions of estrogen-alone therapy such as headache, breast pain and tenderness, nausea, and vomiting. Trademarks are the property of their respective owners. Distributed by: ANI Pharmaceuticals, Inc.
Baudette, MN 56623 LB4567-02 Revised: 02/2024