Generic name: Letrozole.

Femara is an estrogen anticancer blocker. It reduces the amount of estradiol (an estrogenic hormone) circulating in the body. It does this by suppressing the production of the aromatase enzyme, which is an element in the manufacture of estradiol. 

Quick Facts About Femara


Used to treat postmenopausal women with advanced breast cancer that has spread to other parts of the body following treatment with tamoxifen (Nolvadex). May prolong survival and improve quality of life when taken exactly as prescribed, even if you don’t feel well.

Femara Dosage

Take exactly as prescribed. Take either 1 hour before or 2 hours after a meal.

  • Usual adult dose: 2.5 milligrams per day.
  • Usual child dose: not prescribed for children.
  • Missed dose: take within 12 hours of missed dose. Otherwise, do not take missed dose; go back to regular schedule. Do not double doses.

Femara Side Effects

Overdose symptoms:

none reported. However, if you suspect an overdose, immediately seek medical attention. Always bring the prescription bottle or container with you.

More common side effects: abdominal pain, back pain, bone pain, constipation, cough, diarrhea, dizziness, dry mouth, headache, hot flashes, loss of appetite, nausea, pain, “pins and needles”, rash, shortness of breath, sore throat, vomiting, weakness, weight gain.

Less common Femara side effects: appetite loss, chest pain, depression, numbness, pelvic pain, swelling of arms and legs. Rare side effects: accidental injury, anxiety, blood clots (symptoms include severe leg pain), breast pain, bronchitis, confusion, drowsiness, feeling of illness, fever, flu-like symptoms, fractures, hair thinning, high blood pressure, increased appetite, infection, insomnia, itching, joint pain, muscle pain, nasal or sinus inflammation, neck pain, nervousness, sweating, urinary tract infection, vaginal hemorrhage, weight loss.


No known Femara drug interactions

No known food/other substance interactions. 

Special Cautions

If pregnant or planning to become pregnant, inform your doctor immediately. Femara has shown significant harm to the fetus in animal studies. May cause severe birth defects and be poisonous to your unborn child. It may also increase likelihood of miscarriage or stillbirth. Not known if Femara appears in breast milk; could affect a nursing infant.

No special precautions apply to seniors.

Not prescribed for children.

  • It is extremely important to follow your doctor’s exact dosage schedule instructions. Do not deviate from this schedule or discontinue use unless directed by your doctor. Inform your doctor immediately if more than two doses in a row are missed.
  • Inform your doctor immediately if side effects become severe or uncomfortable. He or she may be able to recommend ways to reduce discomfort.
  • May raise the level of cholesterol in blood. Doctor may periodically do blood tests to check.
  • Use a condom, diaphragm, or other nonhormonal contraceptive while taking Femara.


HealthSurvey.org provides accurate and independent information prescription pills, over-the-counter medicines and natural products. This material is provided for educational purposes only and is not intended for medical advice, diagnosis or treatment. If you have questions about  dosage, or Femara side effects, please contact your healthcare provider.