What is this medicine?
LETROZOLE (LET roe zole) blocks the production of estrogen. It is used to treat breast cancer.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): Femara
What should I tell my health care provider before I take this medicine?
They need to know if you have any of these conditions:
- high cholesterol
- liver disease
- osteoporosis (weak bones)
- an unusual or allergic reaction to letrozole, other medicines, foods, dyes, or preservatives
- pregnant or trying to get pregnant
How should I use this medicine?
Take this medicine by mouth with a glass of water. You may take it with or without food. Follow the directions on the prescription label. Take your medicine at regular intervals. Do not take your medicine more often than directed. Do not stop taking except on your doctor's advice.
Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.
Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.
What if I miss a dose?
If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.
What may interact with this medicine?
Do not take this medicine with any of the following medications:
- estrogens, like hormone replacement therapy or birth control pills
This medicine may also interact with the following medications:
- dietary supplements such as androstenedione or DHEA
This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.
What should I watch for while using this medicine?
Tell your doctor or healthcare professional if your symptoms do not start to get better or if they get worse.
Do not become pregnant while taking this medicine or for 3 weeks after stopping it. Women should inform their doctor if they wish to become pregnant or think they might be pregnant. There is a potential for serious side effects to an unborn child. Talk to your health care professional or pharmacist for more information. Do not breast-feed while taking this medicine or for 3 weeks after stopping it.
This medicine may interfere with the ability to have a child. Talk with your doctor or health care professional if you are concerned about your fertility.
Using this medicine for a long time may increase your risk of low bone mass. Talk to your doctor about bone health.
You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells.
You may need blood work done while you are taking this medicine.
What side effects may I notice from receiving this medicine?
Side effects that you should report to your doctor or health care professional as soon as possible:
- allergic reactions like skin rash, itching, or hives
- bone fracture
- chest pain
- signs and symptoms of a blood clot such as breathing problems; changes in vision; chest pain; severe, sudden headache; pain, swelling, warmth in the leg; trouble speaking; sudden numbness or weakness of the face, arm or leg
- vaginal bleeding
Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):
- bone, back, joint, or muscle pain
- fluid retention
- hot flashes, night sweats
- weight gain
This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
Where should I keep my medicine?
Keep out of the reach of children.
Store between 15 and 30 degrees C (59 and 86 degrees F). Throw away any unused medicine after the expiration date.
NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.
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