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Medication Guide — Cenestin Estrogens Conjugated Synthetic A 0 45 Mg

Patient-friendly FDA guidance and safety information.

Last updated · May 16, 2026Source: DailyMed ↗
Boxed Warning

Close clinical surveillance of all women taking estrogens is important. Adequate diagnostic measures, including endometrial sampling when indicated, should be undertaken to rule out malignancy in all cases of undiagnosed persistent or recurring abnormal vaginal bleeding. There is no evidence that the use of “natural” estrogens results in a different endometrial risk profile than synthetic estrogens at equivalent estrogen doses. (See WARNINGS, Malignant neoplasms, Endometrial cancer .)

CARDIOVASCULAR AND OTHER RISKS

Estrogens with and without progestins should not be used for the prevention of cardiovascular disease. (See WARNINGS, Cardiovascular disorders .)

The Women’s Health Initiative (WHI) study reported increased risks of myocardial infarction, stroke, invasive breast cancer, pulmonary emboli, and deep vein thrombosis in postmenopausal women (50 to 79 years of age) during 5 years of treatment with oral conjugated equine estrogens (CE 0.625 mg) combined with medroxyprogesterone acetate (MPA 2.5 mg) relative to placebo. (See CLINICAL PHARMACOLOGY, Clinical Studies .)

The Women’s Health Initiative Memory Study (WHIMS), a substudy of WHI, reported increased risk of developing probable dementia in postmenopausal women 65 years of age or older during 4 years of treatment with oral conjugated estrogens plus medroxyprogesterone acetate relative to placebo. It is unknown whether this finding applies to younger postmenopausal women. (See CLINICAL PHARMACOLOGY, Clinical Studies .)

Other doses of oral conjugated estrogens with medroxyprogesterone acetate, and other combinations and dosage forms of estrogens and progestins were not studied in the WHI clinical trials and, in the absence of comparable data, these risks should be assumed to be similar. Because of these risks, estrogens with or without progestins should be prescribed at the lowest effective doses and for the shortest duration consistent with treatment goals and risks for the individual woman.

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PATIENT INFORMATION

Cenestin®

(synthetic conjugated estrogens, A) Tablets

Read this PATIENT INFORMATION before you start taking Cenestin and read what you get each time you refill Cenestin. There may be new information. This information does not take the place of talking to your healthcare provider about your medical condition or your treatment.

WHAT IS THE MOST IMPORTANT INFORMATION I SHOULD KNOW ABOUT CENESTIN (SYNTHETIC ESTROGEN MIXTURE)?

• Estrogens increase the chances of getting cancer of the uterus.

Report any unusual vaginal bleeding right away while you are taking estrogens. Vaginal bleeding after menopause may be a warning sign of cancer of the uterus (womb).Your healthcare provider should check any unusual vaginal bleeding to find out the cause.

• Do not use estrogens with or without progestins to prevent heart disease, heart attacks, or strokes.

Using estrogens with or without progestins may increase your chances of getting heart attacks, strokes, breast cancer, and blood clots. Using estrogens with progestins may increase your risk of dementia. You and your healthcare provider should talk regularly about whether you still need treatment with Cenestin.

What is Cenestin?

Cenestin is a medicine that contains a mixture of synthetic estrogens made from a plant source.

What is Cenestin used for?

Cenestin is used after menopause to:

  • reduce moderate or severe hot flashes.
    Estrogens are hormones made by a woman’s ovaries. The ovaries normally stop making estrogens when a woman is between 45 to 55 years old. This drop in body estrogen levels causes the “change of life” or menopause (the end of monthly menstrual periods). Sometimes, both ovaries are removed during an operation before natural menopause takes place. The sudden drop in estrogen levels causes “surgical menopause.”
    When estrogen levels begin dropping, some women develop very uncomfortable symptoms, such as feelings of warmth in the face, neck, and chest, or sudden strong feelings of heat and sweating (“hot flashes” or “hot flushes”). In some women, the symptoms are mild, and they will not need estrogens. In other women, symptoms can be more severe. You and your healthcare provider should talk regularly about whether you still need treatment with Cenestin.
  • treat moderate to severe dryness, itching, and burning in and around the vagina. You and your healthcare provider should talk regularly about whether you still need treatment with Cenestin to control these problems. If you use Cenestin only to treat your dryness, itching, and burning in and around your vagina, talk with your healthcare provider about whether a topical vaginal product would be better for you.

Who Should Not Take Cenestin?

Do not start taking Cenestin if you:

  • have unusual vaginal bleeding.
  • currently have or have had certain cancers.
    Estrogens may increase the risk of certain types of cancers, including cancer of the breast or uterus. If you have or had cancer, talk with your healthcare provider about whether you should take Cenestin.
  • had a stroke or heart attack in the past year.
  • currently have or have had blood clots.
  • currently have or have had liver problems.
  • are allergic to Cenestin or any of its ingredients.
    See the end of this leaflet for a list of ingredients in Cenestin.
  • if you think you may be pregnant.

Tell your healthcare provider:

  • if you are breastfeeding.
    The synthetic estrogen hormones in Cenestin can pass into your milk.
  • about all of your medical problems.
    Your healthcare provider may need to check you more carefully if you have certain conditions, such as asthma (wheezing), epilepsy (seizures), migraine, endometriosis, lupus, or problems with your heart, liver, thyroid, kidneys, or have high calcium levels in your blood.
  • about all the medicines you take.
    This includes prescription and nonprescription medicines, vitamins, and herbal supplements. Some medicines may affect how Cenestin works. Cenestin may also affect how your other medicines work.
  • if you are going to have surgery or will be on bedrest.
    You may need to stop taking estrogens.

How Should I Take Cenestin?

Take one Cenestin tablet each day at about the same time. If you miss a dose, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your normal schedule. Do not take 2 doses at the same time.

Start at the lowest dose and talk to your healthcare provider about how well that dose is working for you. Estrogens should be used only as long as needed. You and your healthcare provider should talk regularly (for example every 3 to 6 months) about whether you still need treatment with Cenestin.

What are the possible side effects of estrogens?

Less common but serious side effects include:

These are some of the warning signs of serious side effects:

  • Breast lumps
  • Chest pain
  • Unusual vaginal bleeding
  • Shortness of breath
  • Dizziness and faintness
  • Pains in your legs
  • Changes in speech
  • Changes in vision
  • Severe headaches
  • Vomiting

Call your healthcare provider right away if you get any of these warning signs, or any other unusual symptom that concerns you.

Common side effects include:

  • Headache
  • Stomach/abdominal cramps, bloating
  • Breast pain
  • Nausea and vomiting
  • Irregular vaginal bleeding or spotting
  • Hair loss

Other side effects include:

  • High blood pressure
  • Fluid retention
  • Liver problems
  • Enlargement of benign tumors of the uterus (“fibroids”)
  • High blood sugar
  • Vaginal yeast infection

These are not all the possible side effects of Cenestin. For more information, ask your healthcare provider or pharmacist.

What can I do to lower my chances of a serious side effect with Cenestin?

  • Talk with your healthcare provider regularly about whether you should continue taking Cenestin.
  • If you have a uterus, talk to your healthcare provider about whether the addition of a progestin is right for you.
  • See your healthcare provider right away if you get vaginal bleeding while taking Cenestin.
  • Have a breast exam and mammogram (breast X-ray) every year unless your healthcare provider tells you something else. If members of your family have had breast cancer or if you have ever had breast lumps or an abnormal mammogram, you may need to have breast exams more often.
  • If you have high blood pressure, high cholesterol (fat in the blood), diabetes, are overweight, or if you use tobacco, you may have higher chances for getting heart disease. Ask your healthcare provider for ways to lower your chances for getting heart disease.

General information about safe and effective use of Cenestin.

Medicines are sometimes prescribed for conditions that are not mentioned in patient information leaflets. Do not take Cenestin for conditions for which it was not prescribed. Do not give Cenestin to other people, even if they have the same symptoms you have. It may harm them.

Keep Cenestin out of the reach of children.

This leaflet provides a summary of the most important information about Cenestin. If you would like more information, talk with your healthcare provider or pharmacist. You can ask for information about Cenestin that is written for health professionals. You can get more information by calling the toll free number 877-405-0369.

What are the ingredients in Cenestin?

Tablets for oral administration, are available in 0.3 mg, 0.45 mg, 0.625 mg, 0.9 mg and 1.25 mg strengths of synthetic conjugated estrogens, A. Tablets also contain the following inactive ingredients: ethylcellulose, hypromellose, lactose monohydrate, magnesium stearate, polyethylene glycol, polysorbate 80, pregelatinized starch, titanium dioxide, and triethyl citrate.

-0.3 mg tablets also contain FD&C Blue No. 2 aluminum lake and D&C Yellow No. 10 aluminum lake.

-0.45 mg tablets also contain FD&C Yellow No. 6/Sunset Yellow FCF lake.

-0.625 mg tablets also contain FD&C Red No. 40 aluminum lake.

-0.9 mg tablets do not contain any additional color additives.

-1.25 mg tablets also contain FD&C Blue No. 2 aluminum lake.

Manufactured By:

Duramed Pharmaceuticals, Inc.

Subsidiary of Barr Pharmaceuticals, Inc.

Pomona, New York 10970

Revised SEPTEMBER 2004

BR - 41, 46, 42, 43, 44

Relabeling and Repackaging by:
Physicians Total Care, Inc.
Tulsa, OK      74146

Sources

RxCUI: 540391

NDC: 512850446

Last fetched: May 16, 2026

Source: DailyMed ↗

⚠️ Disclaimer

This information is for educational purposes only and is not medical advice. Always consult your doctor, pharmacist, or other licensed healthcare professional before starting, stopping, or changing any medicine. Read full medical disclaimer.