What are the side effects of estrogens conjugated, synthetic?
Common side effects of conjugated estrogens are:
Other important side effects are:
- vaginal spotting,
- loss of periods or
- excessively prolonged periods,
- breast pain,
- breast enlargement, and
- an increase or decrease in sexual drive.
Estrogens can cause salt (sodium) and water retention (edema). Therefore, patients with heart failure or reduced function of their kidneys who are taking estrogens should be carefully observed for retention of water and its complications.
Blood clots in the legs or lungs occasionally occur in women taking conjugated estrogens. This potentially serious complication of estrogen therapy is dose-related, that is, it occurs more commonly with higher doses. Therefore, the lowest effective doses that relieve symptoms should be used. Cigarette smokers are at a higher risk for blood clots. Therefore, patients requiring estrogen therapy should quit smoking.
Estrogens can promote a build up of the lining of the uterus (endometrial hyperplasia) and increase the risk of endometrial cancer. (Women who have undergone surgical removal of the uterus (hysterectomy) are not susceptible to endometrial hyperplasia.) The addition of a progestin to estrogen therapy prevents the development of endometrial cancer.
The Women’s Health Initiative found that postmenopausal women (50-79 years old) taking conjugated estrogens, 0.625 mg daily, in combination with medroxyprogesterone, 2.5 mg daily, for five years, had an increased risk of heart attacks, stroke, breast cancer, and blood clots, while postmenopausal women taking conjugated estrogens without progesterone experienced only increased strokes but not increased blood clots, heart disease, or breast cancer.