What is this medication?
TAMOXIFEN (ta MOX i fen) prevents and treats breast cancer. It works by blocking the hormone estrogen in breast tissue, which prevents breast cancer cells from spreading or growing.
This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.
COMMON BRAND NAME(S): Nolvadex
What should I tell my care team before I take this medication?
They need to know if you have any of these conditions:
- Blood clots
- High cholesterol
- Irregular menstrual cycles
- Liver disease
- Uterine cancer
- Uterine fibroids
- An unusual reaction to tamoxifen, other medications, foods, dyes, or preservatives
- Pregnant or trying to get pregnant
How should I use this medication?
Take this medication by mouth. Take it as directed on the prescription label at the same time every day. You can take it with or without food. If it upsets your stomach, take it with food. Keep taking it unless your care team tells you to stop.
A special MedGuide will be given to you by the pharmacist with each prescription and refill. Be sure to read this information carefully each time.
Talk to your care team about the use of this medication 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 medication?
Do not take this medication with any of the following:
This medication may also interact with the following:
- Certain medications for seizures like carbamazepine, phenobarbital, phenytoin
- Other medications that prolong the QT interval
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 medication?
Visit your care team for regular checks on your progress. You will need regular pelvic exams, breast exams, and mammograms.
Talk to your care team about your risk of uterine cancer. You may be more at risk for uterine cancer if you take this medication.
Do not become pregnant while taking this medication or for 2 months after stopping it. Women should inform their care team if they wish to become pregnant or think they might be pregnant. There is a potential for serious harm to an unborn child. Talk to your care team for more information. Do not breast-feed an infant while taking this medication or for 3 months after stopping it.
This medication may make it more difficult to get pregnant. Talk with your care team if you are concerned about your fertility.
What side effects may I notice from receiving this medication?
Side effects that you should report to your care team as soon as possible:
- Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
- Blood clot—pain, swelling, or warmth in the leg, shortness of breath, chest pain
- High calcium level—increased thirst or amount of urine, nausea, vomiting, confusion, unusual weakness or fatigue, bone pain
- Infection—fever, chills, cough, or sore throat
- Irregular menstrual cycles or spotting
- Liver injury—right upper belly pain, loss of appetite, nausea, light-colored stool, dark yellow or brown urine, yellowing skin or eyes, unusual weakness or fatigue
- Low red blood cell count—unusual weakness or fatigue, dizziness, headache, trouble breathing
- Stroke—sudden numbness or weakness in the face, arm, or leg, trouble speaking, confusion, trouble walking, loss of balance or coordination, dizziness, severe headache, change in vision
- Unusual bruising or bleeding
- Vaginal bleeding after menopause, pelvic pain
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
- Hot flashes
- Mood swings
- Vaginal discharge
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 medication?
Keep out of the reach of children and pets.
Store at room temperature between 20 and 25 degrees C (68 and 77 degrees F). Protect from light. Get rid of any unused medication after the expiration date.
To get rid of medications that are no longer needed or have expired:
- Take the medication to a medication take-back program. Check with your pharmacy or law enforcement to find a location.
- If you cannot return the medication, check the label or package insert to see if the medication should be thrown out in the garbage or flushed down the toilet. If you are not sure, ask your care team. If it is safe to put it in the trash, empty the medication out of the container. Mix the medication with cat litter, dirt, coffee grounds, or other unwanted substance. Seal the mixture in a bag or container. Put it in the trash.
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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