|What are the possible side effects of
Conjugated estrogens 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 conjugated
estrogens lowers the risk of developing this condition. Therefore, if
your uterus has not been removed, your doctor may prescribe a progestin
for you to take together with the estrogen. Visit your doctor regularly
and report any unusual vaginal bleeding right away.
Treatment with conjugated estrogens may increase the risk of heart
attack, stroke, breast cancer, and blood clots in the lungs or legs.
Because of these risks, conjugated estrogens should be prescribed at the
lowest effective dose, for the shortest amount of time necessary.
If you experience any of the following serious side effects, stop taking
conjugated estrogens and seek emergency medical attention:
An allergic reaction (difficulty breathing; closing of the throat;
swelling of the lips, tongue, or face; or hives); shortness or breath or
pain in the chest; a painful, red, or swollen leg; abnormal vaginal
bleeding; pain, swelling, or tenderness in the abdomen; severe headache
or vomiting, dizziness, faintness or changes in vision or speech;
yellowing of the skin or eyes; or a lump in a breast.
Other, less serious side effects may be more likely to occur. Continue
to take conjugated estrogens and talk to your doctor if you experience
decreased appetite, nausea, or vomiting; swollen or tender breasts; acne
or skin color changes; decreased sex drive; migraine headaches or
dizziness; water retention (swollen hands, feet, or ankles); problems
with wearing contact lenses; depression; or changes in menstrual cycle
or breakthrough bleeding.
Side effects other than those listed here may also occur. Talk to your
doctor about any side effect that seems unusual or that is especially
What other drugs will affect conjugated estrogens?
Before taking conjugated estrogens, tell your doctor if you are taking
any of the following medicines: an anticoagulant (blood thinner) such as
warfarin (Coumadin); a thyroid medication such as levothyroxine
(Synthroid, Levoxyl, Levothroid, and others); insulin or an oral
diabetes medicine such as glipizide (Glucotrol) or glyburide (Diabeta,
Micronase); tamoxifen (Nolvadex); didanosine (Videx); phenytoin
(Dilantin) or ethotoin (Peganone); carbamazepine (Tegretol);
phenobarbital (Solfoton, Luminal); primidone (Mysoline); or rifampin
A dosage adjustment or special monitoring may be required during
treatment if you are taking any of the medicines listed above.
Drugs other than those listed here may also interact with conjugated
estrogens. Talk to your doctor and pharmacist before taking any
prescription or over-the-counter medicines, including herbal products.