estrogens conjugated synthetic (Cenestin)

What is estrogens conjugated, synthetic, and how does it work (mechanism of action)?

Cenestin is a combination of nine estrogens. Estrogens are hormones produced by the ovaries that are necessary for the proper development of the female reproductive system and sexual characteristics. After menopause, there is a decrease in the amount of estrogen that is produced by the ovaries. This decrease in estrogen production is responsible for hot flashes, mood changes, sleep disturbance, decreased sexual function and other symptoms associated with menopause. Estrogen deficiency also has been linked to heart disease and bone loss (osteoporosis). Cenestin is similar to conjugated estrogens (Premarin), the other drug used for treating hot flashes. Unlike the estrogens in Premarin which are obtained from natural sources and blended to approximate the composition of estrogens found in urine of pregnant horses, the estrogens in Cenestin are synthetic (man- made) and are produced from plant material. Therefore, the estrogens in Cenestin are different from the estrogens found in Premarin. The FDA approved Cenestin in March 1999.

What brand names are available for estrogens conjugated, synthetic?

Cenestin

Is estrogens conjugated, synthetic available as a generic drug?

GENERIC AVAILABLE: No

Do I need a prescription for estrogens conjugated, synthetic?

Yes

What are the side effects of estrogens conjugated, synthetic?

Common side effects of conjugated estrogens are:

Other important side effects are:

  • vaginal spotting,
  • loss of periods or
  • excessively prolonged periods,
  • breast pain,
  • breast enlargement, and
  • an increase or decrease in sexual drive.
Effects of estrogen on the skin include rash, and melasma (tan or brown patches) that may develop on the forehead, cheeks, or temples and may persist even after estrogens are stopped.

In the eyes, conjugated estrogens may cause an increase in the curvature of the cornea, and, as a result, patients with contact lenses may develop intolerance to their contact lenses.

Estrogens may increase calcium levels in the blood (hypercalcemia) in patients with breast and bone cancer. Some patients may experience increased blood pressure and triglyceride levels.

There is an increased risk of cholesterol gallstones among men and women taking estrogens.

Estrogens also may inhibit the flow of bile from the liver (cholestasis) and uncommonly cause jaundice.

Estrogens can cause salt (sodium) and water retention (edema). Therefore, patients with heart failure or reduced function of their kidneys who are taking estrogens should be carefully observed for retention of water and its complications.

Blood clots in the legs or lungs occasionally occur in women taking conjugated estrogens. This potentially serious complication of estrogen therapy is dose-related, that is, it occurs more commonly with higher doses. Therefore, the lowest effective doses that relieve symptoms should be used. Cigarette smokers are at a higher risk for blood clots. Therefore, patients requiring estrogen therapy should quit smoking.

Estrogens can promote a build up of the lining of the uterus (endometrial hyperplasia) and increase the risk of endometrial cancer. (Women who have undergone surgical removal of the uterus (hysterectomy) are not susceptible to endometrial hyperplasia.) The addition of a progestin to estrogen therapy prevents the development of endometrial cancer.

The Women's Health Initiative found that postmenopausal women (50-79 years old) taking conjugated estrogens, 0.625 mg daily, in combination with medroxyprogesterone, 2.5 mg daily, for five years, had an increased risk of heart attacks, stroke, breast cancer, and blood clots, while postmenopausal women taking conjugated estrogens without progesterone experienced only increased strokes but not increased blood clots, heart disease, or breast cancer.

There was an increased risk of impaired cognition and/or dementia among women over age 65 treated with either estrogens or estrogens and medroxyprogesterone.

SLIDESHOW

What Is Osteoporosis? Treatment, Symptoms, Medication See Slideshow

What is the dosage for estrogens conjugated, synthetic?

The lowest effective dose should be used, starting with 0.45 mg and gradually increasing to 1.25 mg a day for treatment of hot flashes and 0.3 mg for treatment of vulvar and vaginal atrophy.

Is estrogens conjugated, synthetic safe to take if I'm pregnant or breastfeeding?

Estrogens such as Cenestin may decrease the quantity and quality of breast milk and produce unpredictable effects in the infant. Nursing mothers should avoid taking estrogens.

What else should I know about estrogens conjugated, synthetic?

What preparations of estrogens conjugated, synthetic are available?

Tablets: 0.3, 0.45, 0.625, 0.9, and 1.25 mg

How should I keep estrogens conjugated, synthetic stored?

Tablets should be stored at room temperature, 15 C to 30 C (59 F to 86 F).

Summary

Estrogens conjugated synthetic (Cenestin) is a combination of estrogens prescribed for the relief of moderate to severe hot flashes and vaginal atrophy. Side effects, drug interactions, and pregnancy information should be reviewed prior to taking this medication.

Treatment & Diagnosis

Medications & Supplements

Prevention & Wellness

QUESTION

If menopause occurs in a woman younger than ___ years, it is considered to be premature. See Answer

Health Solutions From Our Sponsors

FDA Logo

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

References
Medically reviewed by John P. Cunha, DO, FACOEP; Board Certified Emergency Medicine

REFERENCES:

FDA Prescribing Information