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Conjugated estrogens (Oral)

Generic name: conjugated estrogens [ KON-joo-gay-ted-ES-troe-jenz ]
Brand name: Premarin
Drug class: Estrogens

Medically reviewed by Drugs.com. Last updated on Aug 6, 2024.

Oral route(Tablet)

Endometrial Cancer, Cardiovascular Disorders, Breast Cancer and Probable Dementia

Estrogen-Alone Therapy

There is an increased risk of endometrial cancer in a woman with a uterus who uses unopposed estrogens.

Estrogen-alone therapy should not be used for the prevention of cardiovascular disease or dementia.

Women's Health Initiative estrogen-alone substudy reported increased risks of stroke and deep vein thrombosis.

The Women’s Health Initiative Memory Study estrogen-alone ancillary study of Women’s Health Initiative reported an increased risk of probable dementia in postmenopausal women 65 years of age and older.

Estrogen Plus Progestin Therapy

Estrogen plus progestin therapy should not be used for the prevention of cardiovascular disease or dementia.

The Women’s Health Initiative estrogen plus progestin substudy reported increased risks of stroke, DVT, pulmonary embolism, and myocardial infarction.

The Women’s Health Initiative estrogen plus progestin substudy reported increased risks of invasive breast cancer.

The Women’s Health Initiative Memory Study estrogen plus progestin ancillary study of Women’s Health Initiative reported an increased risk of probable dementia in postmenopausal women 65 years of age and older .

Uses for conjugated estrogens

Conjugated estrogens are a medicine that contains a mixture of estrogen hormones. It is used to treat moderate to severe hot flashes, changes in and around the vagina, and other symptoms of menopause or low amounts of estrogen (hypoestrogenism). This medicine is also used to prevent osteoporosis (thinning of the bones) after menopause.

Conjugated estrogens tablet is also used to treat symptoms of breast and prostate cancer that have spread through the body in men and women. It is also used to treat certain conditions in women before menopause if their ovaries do not make enough estrogen naturally.

This medicine is available only with your doctor's prescription.

Before using conjugated estrogens

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies on the relationship of age to the effects of conjugated estrogens have not been performed in the pediatric population. However, pediatric-specific problems that would limit the usefulness of this medication in teenagers are not expected.

Geriatric

Although appropriate studies on the relationship of age to the effects of conjugated estrogens have not been performed in the geriatric population, no geriatric-specific problems have been documented to date. However, elderly patients are more likely to have breast cancer, stroke, or dementia, which may require caution in patients receiving conjugated estrogens.

Breast Feeding

Studies suggest that this medication may alter milk production or composition. If an alternative to this medication is not prescribed, you should monitor the infant for side effects and adequate milk intake.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

Proper use of conjugated estrogens

It is very important that you use this medicine only as directed by your doctor. Do not use more of it, do not use it more often, and do not use it for a longer time than your doctor ordered. To do so may cause unwanted side effects.

This medicine comes with a patient information leaflet. Read and follow the instructions in the leaflet carefully. Ask your doctor if you have any questions.

You may take this medicine with or without food.

It is important that you eat a well-balanced diet with an adequate amount of calcium and vitamin D (found in milk or other dairy products). It is recommended that you receive calcium and vitamin D supplements while receiving this medicine.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

alendronate, estradiol, tamoxifen, Prolia, Fosamax, calcium carbonate, testosterone, Premarin, norethindrone

Precautions while using conjugated estrogens

It is very important that your doctor check your progress at regular visits to make sure this medicine is working properly and does not cause unwanted effects. Pelvic exam, breast exam, and mammogram (breast x-ray) may be needed to check for unwanted effects, unless your doctor tells you otherwise.

Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using the medicine, tell your doctor right away.

Using large doses of this medicine over a long period of time may increase your risk of heart attack, stroke, blood clots, dementia, breast cancer, or uterine cancer. Talk with your doctor about this risk. If you still have your uterus (womb), ask your doctor if you should also use a progestin medicine.

Your risk of heart disease or stroke from this medicine is higher if you smoke. Your risk is also increased if you have diabetes or high cholesterol, or if you are overweight. Talk with your doctor about ways to stop smoking. Keep your diabetes under control. Ask your doctor about diet and exercise to control your weight and blood cholesterol level.

Tell the medical doctor or dentist in charge that you are using this medicine before any kind of surgery (including dental surgery) or emergency treatment. Your doctor will decide whether you should continue using this medicine.

Using this medicine alone may increase your risk of getting cancer of the uterus (womb). Check with your doctor right away if you have unusual vaginal bleeding while you are using this medicine.

Stop using this medicine and check with your doctor immediately if severe headache or sudden loss of vision or any other change in vision occurs while you are using this medicine. Your doctor may want you to have your eyes checked by an ophthalmologist (eye doctor).

This medicine may cause a serious type of allergic reaction called anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Call your doctor right away if you have a rash; itching; hoarseness; trouble breathing; trouble swallowing; or any swelling of your hands, face, mouth, or throat while you are using this medicine.

Before you have any medical tests, tell the medical doctor in charge that you are taking this medicine. The results of some tests may be affected by this medicine.

Side Effects of conjugated estrogens

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

Less common

Incidence not known

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Less common

Incidence not known

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Commonly used brand name(s)

In the U.S.

Available Dosage Forms:

Therapeutic Class: Endocrine-Metabolic Agent

Pharmacologic Class: Estrogen

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.