What is esterified estrogens and methyltestosterone, and how does it work (mechanism of action)?

Esterified estrogens are a mixture of related estrogens. Estrogens, when taken alone or in combination with a progestin, have been shown to reduce the risk for hip fracture due to osteoporosis by 25% as well as the risk of heart attack (myocardial infarction) and stroke by 40-50%. Esterified estrogens are used for numerous medical situations. Estrogens cause growth and development of female sex organs and the maintain sex characteristics, including growth of underarm and pubic hair and shaping of body contours and skeleton. Estrogens also increase secretions from the cervix and growth of the inner lining of the uterus (endometrium). Estrogens reduce LDL-cholesterol (“bad” cholesterol) and increase HDL-cholesterol (“good” cholesterol) concentrations.

Testosterone is the major male sex hormone that is responsible for many male sexual characteristics, but women also produce small amounts of testosterone. Following menopause, a woman’s production of testosterone decreases. When testosterone in the form of methyltestosterone is added to estrogens, there may be a further alleviation of the hot flashes seen after menopause, and there also may be an improvement in a woman’s sexual function.

What brand names are available for esterified estrogens and methyltestosterone?

Estratest (discontinued), Covaryx, Covaryx H.S., EEMT HS, EEMT

Is esterified estrogens and methyltestosterone available as a generic drug?


Do I need a prescription for esterified estrogens and methyltestosterone?


What are the side effects of esterified estrogens and methyltestosterone?

For side effects, please read the esterified estrogens article.

Important side effects of methyltestosterone can have masculinizing effects in women, including:

  • the development of acne,
  • growth of facial hair,
  • enlargement of the clitoris,
  • reduction in breast size, and
  • deepening of the voice.

If treatment is discontinued when these symptoms first appear, they usually diminish or disappear; however, prolonged treatment can cause irreversible masculinizing effects.

What is the dosage for esterified estrogens and methyltestosterone?

Estratest usually is prescribed as 1 or 2 tablets daily for 21 consecutive days followed by 7 days without medication.

Which drugs or supplements interact with esterified estrogens and methyltestosterone?

For drug interactions for esterified estrogens, please read the esterified estrogens article.

Methyltestosterone can increase the effects of warfarin (Coumadin), increasing the risk of bleeding. Taking methyltestosterone and imipramine (Tofranil) together has led to paranoia in a few patients. Methyltestosterone can increase blood concentrations of cyclosporine (Sandimmune; Neoral), which can increase the risk of kidney damage.

Is esterified estrogens and methyltestosterone safe to take if I’m pregnant or breastfeeding?

Both methyltestosterone and estrogens should not be used during pregnancy due to an increased risk of fetal abnormalities.

Estrogens are secreted in milk and cause unpredictable effects in the infant. They should not be used during breast-feeding.

What else should I know about esterified estrogens and methyltestosterone?

What preparations of esterified estrogens and methyltestosterone are available?

Estratest tablets: esterified estrogens 0.625mg plus methyltestosterone 1.25mg; esterified estrogens 1.25mg plus methyltestosterone 2.5mg. Estratest HS is one-half the strength of Estratest.

How should I keep esterified estrogens and methyltestosterone stored?

Tablets should be stored at 36 F – 86 F (20 C – 30 C).

Menopause & Perimenopause: Symptoms, Signs

Medically Reviewed on 12/17/2018


Medically reviewed by John Cunha, DO

Reference: FDA Prescribing Information