Generic name: conjugated estrogens synthetic a [ KON-joo-gay-ted-ES-troe-jenz-sin-THET-ik-A ]
Brand name: Cenestin
Drug class: Estrogens

Medically reviewed by Drugs.com. Last updated on Dec 16, 2023.

Uses for conjugated estrogens synthetic a

Conjugated estrogens synthetic A is used to treat moderate to severe hot flashes and other symptoms of menopause or low amounts of estrogen. It is also used to treat changes in and around the vagina (such as vaginal dryness, itching, and burning) caused by menopause.

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

Before using conjugated estrogens synthetic a

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

Cenestin® is not indicated for use in children.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of Cenestin® in the elderly. However, elderly patients are more likely to have breast cancer, dementia, or stroke, which may require caution in patients receiving this medicine.

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 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.

• Levothyroxine

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:

• Abnormal or unusual vaginal bleeding or
• Blood clots (eg, deep vein thrombosis, pulmonary embolism), active or history of or
• Breast cancer, known or suspected, or a history of or
• Heart attack, active or history of or
• Liver disease or
• Protein C, protein S, or other known blood clotting disorders or
• Stroke, active or history of or
• Surgery with a long period of inactivity or
• Tumors (estrogen-dependent), known or suspected—Should not be used in patients with these conditions.

• Asthma or
• Cancer, history of or
• Diabetes or
• Edema (fluid retention or body swelling) or
• Endometriosis or
• Epilepsy (seizures) or
• Gallbladder disease or
• Hereditary angioedema (swelling of the face, lips, tongue, or throat) or
• Hypercalcemia (high calcium in the blood) or
• Hypertension (high blood pressure) or
• Hypertriglyceridemia (high triglycerides or fats in the blood) or
• Hypocalcemia (low calcium in the blood) or
• Hypothyroidism (an underactive thyroid) or
• Jaundice during pregnancy or from using hormonal therapy in the past or
• Liver tumors or
• Migraine headache or
• Porphyria (an enzyme problem) or
• Systemic lupus erythematosus (SLE)—Use with caution. May make these conditions worse.

Proper use of conjugated estrogens synthetic a

It is very important that you use this medicine exactly 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 carefully. Ask your doctor if you have any questions.

Swallow the tablet whole. Do not crush, break, or chew it. You may take this medicine with or without food.

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.

• For oral dosage form (tablets):
  • For treatment of moderate to severe hot flashes and other symptoms caused by menopause:
    • Adults—At first, 0.45 milligrams (mg) once a day. Your doctor may adjust your dose as needed.
    • Children—Use is not recommended.
  • For treatment of atrophic vaginitis caused by menopause:
    • Adults—0.3 milligrams (mg) once a day.
    • Children—Use is not recommended.

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.

Related/similar drugs

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

Precautions while using conjugated estrogens synthetic a

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. Be sure to keep all appointments.

It is unlikely that a postmenopausal woman may become pregnant. But, you should know that using this medicine while you are pregnant could harm your unborn baby. If you think you have become pregnant while using the medicine, tell your doctor right away.

Using this medicine over a long period of time may increase your risk of breast cancer, endometrial 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. Check with your doctor immediately if your experience abnormal vaginal bleeding.

Using this medicine may increase your risk of dementia, especially in women 65 years of age and older.

Using this medicine may increase your risk for having blood clots, strokes, or heart attacks. This risk may continue even after you stop using the medicine. Your risk for these serious problems is even greater if you have high blood pressure, high cholesterol in your blood, diabetes, or if you are overweight or smoke cigarettes. Contact your doctor immediately if you experience chest pain, confusion, difficulty speaking, double vision, headaches, an inability to move arms, legs or facial muscle, or an inability to speak.

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. This medicine may also affect the results of certain medical tests.

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).

Do not eat grapefruit or drink grapefruit juice while you are using this medicine. Grapefruit and grapefruit juice may change the amount of this medicine that is absorbed in the body.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal (eg, St. John's wort) or vitamin supplements.

Side Effects of conjugated estrogens synthetic a

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

• Bloating or swelling of the face, arms, hands, lower legs, or feet
• cough
• cramps
• difficulty with swallowing
• dizziness
• fast heartbeat
• heavy bleeding
• hives, itching, or skin rash
• itching of the vagina or genital area
• normal menstrual bleeding occurring earlier, possibly lasting longer than expected
• pain during sexual intercourse
• puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• rapid weight gain
• thick, white vaginal discharge with no odor or with a mild odor
• tightness in the chest
• tingling of the hands or feet
• unusual tiredness or weakness
• unusual weight gain or loss

Incidence not known

• Acid or sour stomach
• backache
• belching
• change in vaginal discharge
• clear or bloody discharge from the nipple
• confusion
• decrease in the amount of urine
• difficulty with speaking
• dimpling of the breast skin
• double vision
• headache
• heartburn
• inability to move the arms, legs, or facial muscles
• inability to speak
• indigestion
• inverted nipple
• loss of appetite
• lump in the breast or under the arm
• noisy, rattling breathing
• pain or feeling of pressure in the pelvis
• pain, redness, or swelling in the arm or leg
• persistent crusting or scaling of the nipple
• redness or swelling of the breast
• slow speech
• sore on the skin of the breast that does not heal
• stomach discomfort, upset, or pain
• swelling of the abdominal or stomach area
• swelling of the fingers, hands, feet, or lower legs
• troubled breathing at rest
• vaginal bleeding

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

• Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
• excess air or gas in the stomach or intestines
• fear or nervousness
• heartburn
• increased clear or white vaginal discharge
• indigestion
• lack or loss of strength
• loss of bladder control
• nausea
• passing gas
• runny nose
• sneezing
• stuffy nose
• vomiting

Less common

• Back pain
• increased appetite

Incidence not known

• Breast pain, swelling, or tenderness
• discouragement
• enlarged breasts
• feeling sad or empty
• hair loss or thinning of the hair
• irritability
• lack of appetite
• loss of interest or pleasure
• sleepiness or unusual drowsiness
• tiredness
• trouble concentrating
• trouble sleeping

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.

• Cenestin

Pharmacologic Class: Estrogen

Further information

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

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