ESTRING® Description (estradiol) | Pfizer Medical Information - US

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DESCRIPTION

ESTRING® (estradiol vaginal ring) is a slightly opaque ring with a whitish core containing a drug reservoir of 2 mg estradiol. Estradiol, silicone polymers and barium sulfate are combined to form the ring. When placed in the vagina, ESTRING releases estradiol, approximately 7.5 mcg per 24 hours, in a consistent stable manner over 90 days. ESTRING has the following dimensions: outer diameter 55 mm; cross-sectional diameter 9 mm; core diameter 2 mm. One ESTRING should be inserted into the upper third of the vaginal vault, to be worn continuously for three months.

Estradiol is chemically described as estra-1, 3, 5(10)-triene-3, 17β-diol. The molecular formula of estradiol is C18H24O2 and the structural formula is:

Chemical Structure

The molecular weight of estradiol is 272.39.

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Our scientific content is evidence-based, scientifically balanced and non-promotional. It undergoes rigorous internal medical review and is updated regularly to reflect new information.

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Resources

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WARNINGS: ENDOMETRIAL CANCER, CARDIOVASCULAR DISORDERS, BREAST CANCER AND PROBABLE DEMENTIA

Estrogen-Alone Therapy

Endometrial...

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INDICATIONS AND USAGE

ESTRING is indicated for the treatment of moderate to severe symptoms of vulvar and vaginal atrophy due to menopause.

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DOSAGE AND ADMINISTRATION

One ESTRING (estradiol vaginal ring) is to be inserted as deeply as possible into the upper one-third of the vaginal vault. The ring is to remain in place continuously for three months, after which...

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CONTRAINDICATIONS

ESTRING is contraindicated in women with any of the following conditions:

Undiagnosed abnormal genital bleeding.
Known, suspected, or history of breast cancer.
Known or suspected...

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WARNINGS

See BOXED WARNINGS

ESTRING is a vaginal administered product with low systemic absorption following continuous use for 3 months (see CLINICAL...

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ADVERSE REACTIONS

See BOXED WARNINGS, WARNINGS and PRECAUTIONS

Because...

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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 ESTRING...

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DESCRIPTION

ESTRING® (estradiol vaginal ring) is a slightly opaque ring with a whitish core containing a drug reservoir of 2 mg estradiol. Estradiol, silicone polymers and barium sulfate are combined to form the ring. When...

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CLINICAL PHARMACOLOGY

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...

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CLINICAL STUDIES

Effects on vulvar and vaginal atrophy

Two controlled studies have demonstrated the efficacy of ESTRING (estradiol vaginal ring) in the treatment of...

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HOW SUPPLIED

Each ESTRING (estradiol vaginal ring) is individually packaged in a heat-sealed rectangular pouch consisting of three layers, from outside to inside: polyester, aluminum foil, and low density polyethylene,...

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PATIENT INFORMATION

ESTRING
(estradiol vaginal ring)

Read this Patient Information before you start using ESTRING and each time you get a refill. There may be new information. This...

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PATIENT INFORMATION

ESTRING
(estradiol vaginal ring)

Read this Patient Information before you start using ESTRING and each time you get a refill. There may be new information. This...

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INSTRUCTIONS FOR USE

How should I use ESTRING?

ESTRING is a local estrogen therapy used after menopause to treat moderate to severe menopausal changes in and around the vagina. ESTRING...

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PHYSICIAN'S LEAFLET

Rx only

...

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Resources

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Estring Website for Consumers and Patients

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Estring Website for Healthcare Professionals

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Report Adverse Event

Pfizer Safety

To report an adverse event related to Pfizer-BioNTech COVID-19 Vaccine (also known as COMIRNATY®, COVID-19 mRNA, Vaccine BNT162b2 or BNT162) or Pfizer COVID-19 Treatment (also known as PAXLOVID™ (nirmatrelvir tablets; ritonavir tablets)), and you are not part of a clinical trial* for this product, click the link below to submit your information:

Pfizer Safety Reporting Site

*If you are involved in a clinical trial for either product, adverse events should be reported to your coordinating study site.

If you cannot use the above website or would like to report an adverse event related to a different Pfizer product, please call Pfizer Safety at
(800) 438-1985.

FDA Medwatch

You may also contact the U.S. Food and Drug Administration (FDA) directly to report adverse events or product quality concerns either online at www.fda.gov/medwatchor by calling
(800)-332-1088.