Side Effects

Drug information provided by: Merative, Micromedex®

Women rarely have severe side effects from taking estrogens to replace estrogen. Discuss these possible effects with your doctor:

The prolonged use of estrogens has been reported to increase the risk of endometrial cancer (cancer of the lining of the uterus) in women after menopause. This risk seems to increase as the dose and the length of use increase. When estrogens are used in low doses for less than 1 year, there is less risk. The risk is also reduced if a progestin (another female hormone) is added to, or replaces part of, your estrogen dose. If the uterus has been removed by surgery (total hysterectomy), there is no risk of endometrial cancer, and no need to take an estrogen and progestin combination.

It is not yet known whether the use of estrogens increases the risk of breast cancer in women. Although some large studies show an increased risk, most studies and information gathered to date do not support this idea.

Check with your doctor immediately if any of the following side effects occur:

Check with your doctor as soon as possible if any of the following side effects occur:

More common

  1. Breast pain or tenderness
  2. dizziness or light-headedness
  3. headache
  4. rapid weight gain
  5. swelling of feet and lower legs
  6. vaginal bleeding


  1. Breast lumps
  2. change in vaginal discharge
  3. discharge from nipple
  4. nausea and vomiting
  5. pains in chest, groin, or leg, especially calf
  6. pains in stomach, side, or abdomen
  7. pain or feeling of pressure in pelvis
  8. severe or sudden headache
  9. sudden and unexplained shortness of breath
  10. sudden loss of coordination
  11. sudden slurred speech
  12. sudden vision changes
  13. weakness or numbness in arm or leg
  14. yellow eyes or skin

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

  1. Back pain
  2. bloating or gas
  3. dizziness
  4. general feeling of tiredness
  5. flu-like symptoms
  6. mental depression
  7. muscle aches
  8. nausea—taking tablet with food may decrease
  9. vaginitis

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.