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Conjugated estrogens (synthetic a)

Pronunciation

Generic Name: conjugated estrogens (synthetic a) (CON-ju-gate-ed ESS-tro-jenz)
Brand Name: Cenestin

Conjugated estrogens (synthetic a) should not be used to prevent heart disease, heart attacks, strokes, or dementia. Estrogens with or without progestins have been shown to increase the risk of heart disease (including heart attack), stroke, dementia, serious blood clots (eg, in the lungs or legs), cancer of the uterus, and breast cancer in some women. Tell your doctor right away if you have unusual vaginal bleeding while you use conjugated estrogens (synthetic a). Talk with your doctor if you have questions about the benefits and risks of using conjugated estrogens (synthetic a).

Conjugated estrogens (synthetic a) should be used for the shortest possible time at the lowest effective dose to minimize the risk of these side effects. Talk with your doctor regularly about your need to use conjugated estrogens (synthetic a).


Conjugated estrogens (synthetic a) is used for:

Treating a variety of symptoms due to menopause (hot flashes, vaginal itching, burning, dryness). It may also be used for other conditions as determined by your doctor.

Conjugated estrogens (synthetic a) is a mixture of estrogen hormones. It works by replacing natural estrogens in a woman who can no longer produce enough estrogen.

Do NOT use conjugated estrogens (synthetic a) if:

  • you are allergic to any ingredient in conjugated estrogens (synthetic a)
  • you are pregnant or suspect you may be pregnant
  • you have known or suspected breast cancer or a history of breast cancer
  • you have known or suspected cancer that is estrogen-dependent
  • you have abnormal vaginal bleeding of unknown cause
  • you have liver problems or blood clotting problems (eg, protein C, protein S, or antithrombin deficiency)
  • you have ever had a stroke or heart attack
  • you have blood clots (eg, in the legs or lungs) or a history of blood clots

Contact your doctor or health care provider right away if any of these apply to you.

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Before using conjugated estrogens (synthetic a):

Some medical conditions may interact with conjugated estrogens (synthetic a). Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have had yellowing of the eyes or skinduring pregnancy or with past estrogen use
  • if you have asthma, cancer, a certain blood disorder (porphyria), depression, diabetes, epilepsy (seizures), eye or vision problems, fluid retention or swelling (edema), gallbladder disease, heart disease or other heart problems, high blood pressure, high cholesterol or triglyceride levels, high or low calcium levels in the blood, kidney problems, a certain type of liver growth (hemangioma), migraine headaches, pancreatitis, parathyroid gland problems, or thyroid problems
  • if you have a history of swelling of the face or tongue (angioedema), an abnormal mammogram or breast lumps, endometriosis, ovarian cancer, or a family history of breast cancer
  • if you or a family member has a history of blood clots (eg, in the legs or lungs) or lupus or have been very overweight
  • if you smoke or use tobacco products, you are going to have surgery, or you will be on bed rest
  • if you have had your uterus removed (hysterectomy)

Some MEDICINES MAY INTERACT with conjugated estrogens (synthetic a). Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Clarithromycin, erythromycin, itraconazole, ketoconazole, or ritonavir because they may increase the risk of conjugated estrogens (synthetic a)'s side effects
  • Carbamazepine, phenobarbital, rifampin, or St. John's wort because they may decrease conjugated estrogens (synthetic a)'s effectiveness

This may not be a complete list of all interactions that may occur. Ask your health care provider if conjugated estrogens (synthetic a) may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use conjugated estrogens (synthetic a):

Use conjugated estrogens (synthetic a) as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • An extra patient leaflet is available with conjugated estrogens (synthetic a). Talk to your pharmacist if you have questions about this information.
  • Take conjugated estrogens (synthetic a) by mouth with or without food. If stomach upset occurs, take with food to reduce stomach irritation.
  • Take conjugated estrogens (synthetic a) at the same time each day.
  • Grapefruit and grapefruit juice may increase the risk of conjugated estrogens (synthetic a)'s side effects. Talk to your doctor before including grapefruit or grapefruit juice in your diet while you are taking conjugated estrogens (synthetic a).
  • If you miss a dose of conjugated estrogens (synthetic a), take it as soon as possible. If it is almost time for the next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use conjugated estrogens (synthetic a).

Important safety information:

  • Tell your doctor or dentist that you take conjugated estrogens (synthetic a) before you receive any medical or dental care, emergency care, or surgery.
  • Conjugated estrogens (synthetic a) may cause dark skin patches on your face (melasma). Exposure to the sun may make these patches darker, and you may need to avoid prolonged sun exposure and sunlamps. Consult your doctor regarding the use of sunscreens and protective clothing.
  • If you wear contact lenses and you develop problems with them, contact your doctor.
  • If you will be having surgery or will be confined to a chair or bed for a long period of time (eg, a long plane flight), notify your doctor beforehand. You may need to stop taking conjugated estrogens (synthetic a) at least 4 to 6 weeks beforehand as directed by your doctor.
  • Nonprescription therapy to help prevent bone loss includes a weight-bearing exercise plan, as well as adequate daily calcium and vitamin D intake. Consult your doctor or pharmacist for more details.
  • Diabetes patients - Conjugated estrogens (synthetic a) may affect your blood sugar. Check blood sugar levels closely. Ask your doctor before you change the dose of your diabetes medicine.
  • Conjugated estrogens (synthetic a) may interfere with certain lab tests. Be sure your doctor and lab personnel know you are using conjugated estrogens (synthetic a).
  • Have your blood pressure checked as you have been told by your doctor.
  • Be sure to have regular breast exams and gynecology check-ups. Your doctor will tell you how often to have these. You will also need to do breast self-exams as your doctor has told you. Discuss any questions or concerns with your doctor.
  • Lab tests may be performed while you use conjugated estrogens (synthetic a). These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
  • Use conjugated estrogens (synthetic a) with caution in the ELDERLY; they may be more sensitive to its effects.
  • Conjugated estrogens (synthetic a) should not be used in CHILDREN; safety and effectiveness in children have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: Do not use conjugated estrogens (synthetic a) if you are pregnant. Avoid becoming pregnant while you are taking it. If you think you may be pregnant, contact your doctor right away. Conjugated estrogens (synthetic a) is found in breast milk. If you are or will be breast-feeding while you use conjugated estrogens (synthetic a), check with your doctor. Discuss any possible risks to your baby..

Possible side effects of conjugated estrogens (synthetic a):

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Back pain; bloating; breast pain or tenderness; dizziness; flu-like symptoms; gas; hair loss; headache; increased appetite; indigestion; joint pain; leg cramps; nausea or vomiting; stomach pain, cramps, or bloating; trouble sleeping; vaginal spotting or breakthrough bleeding; weakness; weight gain.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing or swallowing; tightness in the chest; swelling of the mouth, face, lips, throat, or tongue; unusual hoarseness); anxiety; breast discharge or lump in the breast; burning, numbness, or tingling; chest, jaw, or arm pain; confusion; coughing up blood; depression; fainting; increased urination; memory problems; migraine; nipple discharge; not able to control bladder; one-sided weakness; painful or difficult urination; severe or persistent breast pain or tenderness; severe or persistent dizziness, headache, nausea, or vomiting; severe stomach pain; shortness of breath; speech changes; swelling, warmth, numbness, change of color, or pain in a leg or arm; swelling of the hands, legs, or feet; symptoms of liver problems (eg, dark urine, pale stools, persistent loss of appetite, right-sided stomach pain, unusual tiredness, yellowing of the skin or eyes); unusual vaginal bleeding, discharge, itching, or odor; vision changes (eg, double vision, loss of vision).

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately.

Proper storage of conjugated estrogens (synthetic a):

Store conjugated estrogens (synthetic a) at room temperature, between 68 and 77 degrees F (20 and 25 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep conjugated estrogens (synthetic a) out of the reach of children and away from pets.

General information:

  • If you have any questions about conjugated estrogens (synthetic a), please talk with your doctor, pharmacist, or other health care provider.
  • Conjugated estrogens (synthetic a) is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take conjugated estrogens (synthetic a) or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about conjugated estrogens (synthetic a). It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to conjugated estrogens (synthetic a). This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your health care provider for complete information about the risks and benefits of using conjugated estrogens (synthetic a).

Issue Date: June 3, 2015
Database Edition 15.2.1.003
Copyright © 2015 Clinical Drug Information, LLC

Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.

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