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Prefest

Prefest Side Effects

Christina Aungst, PharmD, MWCThienLy Neal, PharmD
Reviewed by Christina Aungst, PharmD, MWC, ThienLy Neal, PharmD
Last reviewed on October 19, 2021

The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.

Common Side Effects

  • Headaches (23%)
  • Cold- or flu-like symptoms (up to 21%)
  • Breast pain (16%)
  • Stomach or back pain (12%)
  • Vaginal bleeding (9%)
  • Joint pain (9%)
  • Menstrual cramps (8%)
  • Sinus pain or swelling (8%)

Less Common Side Effects

  • Vaginal pain
  • Sore throat
  • Depression
  • Fatigue
  • Dizziness
  • Muscle aches
  • Gas

Prefest serious side effects

Contact your healthcare provider immediately if you experience any of the following.

  • Allergic reactions
  • Heart attack: chest pain or tightness, pain that radiates up to your shoulder, arm, neck, or jaw
  • Stroke: sudden trouble talking, walking, or numbness on one side of your body or face
  • Shortness of breath
  • Sudden, severe headaches
  • Breast lumps or pain
  • Unusual or heavy vaginal bleeding

Source: FDA

The following Prefest side effects have also been reported

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

Breast pain or tenderness

dizziness or light-headedness

headache

rapid weight gain

swelling of feet and lower legs

vaginal bleeding

Rare

Breast lumps

change in vaginal discharge

discharge from nipple

nausea and vomiting

pains in chest, groin, or leg, especially calf

pains in stomach, side, or abdomen

pain or feeling of pressure in pelvis

severe or sudden headache

sudden and unexplained shortness of breath

sudden loss of coordination

sudden slurred speech

sudden vision changes

weakness or numbness in arm or leg

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

Back pain

bloating or gas

dizziness

general feeling of tiredness

flu-like symptoms

mental depression

muscle aches

nausea—taking tablet with food may decrease

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.

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