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Synthetic Conjugated Estrogens (B) Oral tablet

It is mostly used as hormone replacement in menopausal women to treat hot flashes

Generic Name: conjugated estrogens

Brand Names: Cenestin, Premarin Intravenous, Premarin, Enjuvia

There is an FDA Alert for this drug. Click here to view it.

What is this medicine?

SYNTHETIC CONJUGATED ESTROGENS (B) (sin THET ic CON ju gate ed ESS troe jenz B) is an estrogen. It is mostly used as hormone replacement in menopausal women to treat hot flashes.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:
  • abnormal vaginal bleeding
  • blood vessel disease or blood clots
  • breast, cervical, endometrial, ovarian, liver, or uterine cancer
  • dementia
  • diabetes
  • endometriosis
  • fibroids
  • gallbladder disease
  • heart disease or recent heart attack
  • high blood pressure
  • high cholesterol
  • high level of calcium in the blood
  • kidney disease
  • liver disease
  • mental depression
  • migraine headaches
  • stroke
  • tobacco smoker
  • an unusual or allergic reaction to estrogens, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. Take your medicine at regular intervals, at the same time each day. Do not take your medicine more often than directed.

A patient package insert for the product will be given with each prescription and refill. Read this sheet carefully each time. The sheet may change frequently.

Talk to your pediatrician regarding the use of this medicine in children. This medicine is not approved for use in children.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medicine?

Do not take this medicine with any of the following medications:
  • aromatase inhibitors like aminoglutethimide, anastrozole, exemestane, letrozole, testolactone
  • metyrapone

This medicine may also interact with the following medications:

  • barbiturates, such as phenobarbital
  • carbamazepine
  • clarithromycin
  • erythromycin
  • grapefruit juice
  • medicines for fungal infections like ketoconazole and itraconazole
  • phenytoin
  • ritonavir
  • St. John's Wort
  • thyroid hormones

What should I watch for while using this medicine?

Visit your health care professional for regular checks on your progress. You will need a regular breast and pelvic exam and Pap smear while on this medicine. You should also discuss the need for regular mammograms with your health care professional, and follow his or her guidelines for these tests.

This medicine can make your body retain fluid, making your fingers, hands, or ankles swell. Your blood pressure can go up. Contact your doctor or health care professional if you feel you are retaining fluid.

If you have any reason to think you are pregnant; stop taking this medicine at once and contact your doctor or health care professional.

Smoking increases the risk of getting a blood clot or having a stroke while you are taking this medicine, especially if you are more than 35 years old. You are strongly advised not to smoke.

If you wear contact lenses and notice visual changes, or if the lenses begin to feel uncomfortable, consult your eye care specialist.

This medicine can increase the risk of developing a condition (endometrial hyperplasia) that may lead to cancer of the lining of the uterus. Taking progestins, another hormone drug, with this medicine lowers the risk of developing this condition. Therefore, if your uterus has not been removed (by a hysterectomy), your doctor may prescribe a progestin for you to take together with your estrogen. You should know, however, that taking estrogens with progestins may have additional health risks. You should discuss the use of estrogens and progestins with your health care professional to determine the benefits and risks for you.

If you are going to have surgery, you may need to stop taking this medicine. Consult your health care professional for advice before you schedule the surgery.


Last Updated: December 17, 2009
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