Before Taking Letrozole,
tell your doctor and pharmacist if you are allergic to letrozole, any other medications, or any of the ingredients in letrozole tablets. Ask your pharmacist for a list of the ingredients.
tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: medications that contain estrogen such as hormone replacement therapy (HRT) and hormonal contraceptives (birth control pills, patches, rings, and injections); raloxifene (Evista); and tamoxifen (Nolvadex).
tell your doctor if you have high cholesterol, osteoporosis (condition in which the bones are fragile and break easily), or liver disease.
you should know that letrozole should only be taken by women who have experienced menopause and cannot become pregnant. However, if you are pregnant or breast-feeding, you should tell your doctor before you begin taking this medication. Letrozole may harm the fetus.
you should know that letrozole may make you drowsy. Do not drive a car or operate machinery until you know how this medication affects you.