What is letrozole, and how does it work (mechanism of action)?
Letrozole is an oral, anti-estrogen drug that is used for treating postmenopausal women with breast cancer. The growth of some breast cancers in postmenopausal women is promoted by estrogens that circulate in the blood, and the adrenal glands are the main source of these circulating estrogens. Letrozole inhibits the enzyme in the adrenal glands (aromatase) that produces the estrogens, estradiol and estrone. Letrozole was approved by the FDA in 1997.
What brand names are available for letrozole?
Is letrozole available as a generic drug?
Do I need a prescription for letrozole?
What are the side effects of letrozole?
The most common side effects with letrozole are:
Cholesterol levels may increase during letrozole therapy. Cholesterol levels should be monitored and some patients may require treatment for high cholesterol levels. Letrozole decreases bone mineral density, increasing the risk of osteoporosis and fractures.
What is the dosage for letrozole?
The recommended dose is 2.5 mg once daily with or without food. Patients with severe liver impairment should receive 2.5 mg every other day.
Which drugs or supplements interact with letrozole?
Tamoxifen reduces blood levels of letrozole when both drugs are administered together. However, in clinical studies the benefit of letrozole was not reduced when administered immediately after tamoxifen. Letrozole is an anti-estrogen drug. Therefore, estrogen containing products counteract the effect of letrozole.
Latest Cancer News
Daily Health News
Is letrozole safe to take if I'm pregnant or breastfeeding?
Letrozole damages the fetus. It should not be taken by pregnant women.
It is not known if letrozole is secreted into breast milk.
What else should I know about letrozole?
What preparations of letrozole are available?
How should I keep letrozole stored?
Tablets should be stored at room temperature, 15 C - 30 C (59 F - 86 F).
Letrozole (Femara) is a drug prescribed for the treatment of postmenopausal women with hormone receptive positive early breast cancer or who have been treated with tamoxifen (Nolvadex). Side effects, drug interactions, and pregnancy information should be reviewed prior to taking this medication.
Multimedia: Slideshows, Images & Quizzes
Related Disease Conditions
Breast cancer is an invasive tumor that develops in the mammary gland. Breast cancer is detected via mammograms, breast self-examination (BSE), biopsy, and specialized testing on breast cancer tissue. Treatment of breast cancer may involve surgery, radiation, hormone therapy, chemotherapy, and targeted therapy. Breast cancer risk may be lowered by managing controllable risk factors.
Endometriosis implants are most commonly found on the ovaries, the Fallopian tubes, outer surfaces of the uterus or intestines, and on the surface lining of the pelvic cavity. They also can be found in the vagina, cervix, and bladder. Endometriosis may not produce any symptoms, but when it does the most common symptom is pelvic pain that worsens just prior to menstruation and improves at the end of the menstrual period. Other symptoms of endometriosis include pain during sex, pain with pelvic examinations, cramping or pain during bowel movements or urination, and infertility. Treatment of endometriosis can be with medication or surgery.
Inflammatory Breast Cancer
Inflammatory breast cancer is an accelerated form of breast cancer that is not usually detected by mammogram or ultrasound. Symptoms of inflammatory breast cancer include pain in the breast, skin change in the breast area, bruise on the breast,sudden swelling of the breast, nipple retraction or discharge, and swelling of the lymph nodes.
Paget Disease of the Breast (Paget's Disease of the Nipple)
Paget's disease is a rare form of cancer that forms in or around the nipple and frequently coexists with breast cancer. The exact cause of Paget's disease is unknown. Symptoms and signs include redness, scaling, and flaking of the nipple skin. A biopsy and imaging studies are needed to diagnose the disease. Treatment may include surgery, radiation, and adjuvant therapy.
Breast Cancer Treatment by Stage
Treatment of breast cancer depends upon the stage of the cancer at the time of diagnosis. Some of the various treatments include: hormone therapy, radiation therapy, surgery, chemotherapy, HER2-targeted therapy, neoadjuvant therapy, and adjuvant therapy.
Treatment & Diagnosis
- Endometriosis FAQs
- How To Reduce Your Medication Costs
- Pharmacy Visit, How To Get The Most Out of Your Visit
- Indications for Drugs: Approved vs. Non-approved
- Drugs: The Most Common Medication Errors
- Medication Disposal
- Dangers of Mixing Medications
- Drugs: Buying Prescription Drugs Online Safely
- Generic Drugs, Are They as Good as Brand-Names?
Medications & Supplements
Prevention & Wellness
- Certain Breast Cancer Drugs Tied to Blood Vessel Damage
- Taking Breast Cancer Prevention Drug Beyond 5 Years May Not Raise Survival
- New Drug May Brighten Outlook for Advanced Breast Cancer
- Smoking May Hinder Common Breast Cancer Treatment
- Longer Use of Certain Drugs Cuts Recurrence for Breast Cancer Survivors
- For Unexplained Infertility, Breast Cancer Drug No Better Than Standard Treatment
- Certain Generic Meds May Help Older Patients With Early Breast Cancer
- New Drug Keeps Common Breast Cancer Under Control Longer: Study
- FDA Approves New Breast Cancer Drug
- Ibrance Approved to Treat Advanced Breast Cancer
- Medicare Subsidy Helps Breast Cancer Patients Afford Treatment
- Breast Cancer Drug May Help Women Fight a Leading Cause of Infertility: Study
- Acupuncture No Better Than 'Sham' Version in Breast-Cancer Drug Study
- Drug May Help Slow Advanced Breast Cancer
- Exercise Might Ease Joint Pain Caused by Breast Cancer Drugs
- New Drug Regimens May Slow Advanced Breast Cancer
- FDA Gives Nod to New Breast Cancer Drug
Health Solutions From Our Sponsors
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
FDA Prescribing Information