Letrozole (Oral Route)

Mayo Clinic Health Manager

Get free personalized health guidance for you and your family.

Get Started

Free

E-Newsletter

Subscribe to receive the latest updates on health topics. About our newsletters

  • Housecall
  • Alzheimer's caregiving
  • Living with cancer

Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

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

Less common
  • Bone fracture
  • Breast pain
  • Chest pain
  • Chills, fever, or flu-like symptoms
  • Mental depression
  • Shortness of breath
  • Swelling of the feet or lower legs
Rare
  • Continuing or severe nervousness
  • Cough
  • Dizziness or lightheadedness
  • Fainting
  • Fast heartbeat
  • Heart attack
  • Increased sweating
  • Nausea
  • Pain in chest, groin, or legs, especially the calves
  • Severe and sudden, unexplained shortness of breath
  • Severe, sudden headache
  • Slurred speech
  • Sudden loss of coordination
  • Sudden, severe weakness or numbness in the arm or leg
  • Vaginal bleeding
  • Vision changes
Incidence not known
  • Black, tarry stools
  • Blindness
  • Blurred vision
  • Burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
  • Chest discomfort
  • Decreased vision
  • Dilated neck veins
  • Extreme fatigue
  • Increased need to urinate
  • Irregular breathing
  • Irregular heartbeat
  • Painful or difficult urination
  • Passing urine more often
  • Sore throat
  • Sores, ulcers, or white spots on the lips or in the mouth
  • Swollen glands
  • Unusual bleeding or bruising
  • Unusual tiredness or weakness
  • Weight gain
  • Wheezing
  • White or brownish vaginal discharge

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
  • Bone pain
  • Hot flashes (sudden sweating and feeling of warmth)
  • Joint pain
  • Muscle pain
Less common
  • Anxiety
  • Confusion
  • Constipation
  • Diarrhea
  • Dry mouth
  • Headache
  • Increased thirst
  • Loss of appetite or weight loss
  • Metallic taste
  • Skin rash or itching
  • Sleepiness
  • Spinning or whirling sensation causing loss of balance
  • Stomach pain or upset
  • Trouble sleeping
  • Vomiting
  • Weakness
Incidence not known
  • Bad, unusual, or unpleasant (after) taste and thirst
  • Being forgetful
  • Change in taste
  • Dryness of skin
  • Hair loss
  • Hives or welts
  • Increased appetite
  • Irritability
  • Nervousness
  • Red, sore eyes
  • Redness of skin
  • Swelling or inflammation of the mouth

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.

Precautions

DR601669

Portions of this document last updated:

Nov. 1, 2009

Source: Drug Information provided by: Micromedex

Copyright © 2010 Thomson Healthcare Inc. All rights reserved. Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes.


Text Size: smaller largerlarger