Type of medicine: antineoplastic (anticancer); aromatase inhibitor; hormone antagonist
Generic and brand names: letrozole, oral; Femara
This medicine is taken by mouth to treat breast cancer in women after menopause (no longer have monthly periods). This treatment is used when the cancer has continued after antiestrogen treatment.
It may be used for other conditions as determined by your healthcare provider.
Before taking this medicine, tell your healthcare provider if you have ever had:
Females of childbearing age: This medicine is not given to pregnant women because it can harm the baby. If you are pregnant, tell your healthcare provider. Do not become pregnant during treatment with this medicine. If you become pregnant, contact your healthcare provider right away. Do not breast-feed while you are receiving this medicine.
Take this medicine once a day with or without food. Taking it with meals may lessen the chance the drug will upset your stomach. Swallow the tablets whole with water. Do not crush or chew the tablets.
Check the label on the medicine for directions about your specific dose. Take this medicine exactly as your healthcare provider prescribes. Taking your medicine at the same time each day helps you remember to take it.
Do not stop taking this medicine until your healthcare provider tells you to.
If you miss a dose, take it as soon as you remember unless it is almost time for the next scheduled dose. In that case, skip the missed dose and take the next one as directed. Do not take double doses. If you are not sure of what to do if you miss a dose, or if you miss more than one dose, contact your healthcare provider.
If you or anyone else has intentionally taken too much of this medicine, call 911 or go to the emergency room right away. If you pass out, have seizures, weakness or confusion, or have trouble breathing, call 911. If you think that you or anyone else may have taken too much of this medicine, call the poison control center. Do this even if there are no signs of discomfort or poisoning. The poison control center number is 800-222-1222.
An acute overdose of this medicine is not likely to cause life-threatening symptoms.
This medicine may make you dizzy or drowsy. Do not drive or operate machinery unless you are fully alert.
You may need to have lab tests and bone density tests while taking this medicine. Keep all appointments for these tests.
If you need emergency care, surgery, or dental work, tell the healthcare provider or dentist you are taking this medicine.
Along with its needed effects, your medicine may cause some unwanted side effects. Some side effects may be very serious. Some side effects may go away as your body adjusts to the medicine. Tell your healthcare provider if you have any side effects that continue or get worse.
Life-threatening (Report these to your healthcare provider right away). If you cannot reach your healthcare provider right away, get emergency medical care or call 911 for help): Allergic reaction (hives; itching; rash; trouble breathing; chest pain or tightness in your chest; swelling of your lips, tongue, and throat).
Serious (report these to your healthcare provider right away): Severe muscle and joint pain; chest pain or pressure; swelling of the hands or feet; irregular heartbeat; sudden numbness or weakness; trouble speaking; trouble breathing; sudden vision changes.
Other: Nausea, tiredness, headache, constipation, hot flashes, vomiting, diarrhea, loss of appetite, vaginal bleeding, breast tenderness, dizziness, trouble sleeping, hair loss.
When you take this medicine with other medicines, it can change the way this or any of the other medicines work. Nonprescription medicines, vitamins, natural remedies, and certain foods may also interact. Using these products together might cause harmful side effects. Talk to your healthcare provider if you are taking:
If you are not sure if your medicines might interact, ask your pharmacist or healthcare provider. Keep a list of all your medicines with you. List all the prescription medicines, nonprescription medicines, supplements, natural remedies, and vitamins that you take. Be sure that you tell all healthcare providers who treat you about all the products you are taking.
Store this medicine at room temperature. Keep the container tightly closed. Protect it from heat, high humidity, and bright light.
This advisory includes selected information only and may not include all side effects of this medicine or interactions with other medicines. Ask your healthcare provider or pharmacist for more information or if you have any questions.
Ask your pharmacist for the best way to dispose of outdated medicine or medicine you have not used. Do not throw medicine in the trash.
Keep all medicines out of the reach of children.
Do not share medicines with other people.