TAMOXIFEN blocks the effects of estrogen. It is commonly used to treat breast cancer. It is also used to decrease the chance of breast cancer coming back in women who have received treatment for the disease. It may also help prevent breast cancer in women who have a high risk of developing breast cancer.

They need to know if you have any of these conditions:

• blood clots
• blood disease
• cataracts or impaired eyesight
• endometriosis
• high calcium levels
• high cholesterol
• irregular menstrual cycles
• liver disease
• stroke
• uterine fibroids
• an unusual or allergic reaction to tamoxifen, other medicines, foods, dyes, or preservatives
• pregnant or trying to get pregnant
• breast-feeding

Take this medicine by mouth with a glass of water. You can take it with or without food. 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.

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.

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.

• aminoglutethimide
• bromocriptine
• chemotherapy drugs
• female hormones, like estrogens and birth control pills
• letrozole
• medroxyprogesterone
• phenobarbital
• rifampin
• warfarin

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.

Visit your doctor or health care professional for regular checks on your progress. You will need regular pelvic exams, breast exams, and mammograms. If you are taking this medicine to reduce your risk of getting breast cancer, you should know that this medicine does not prevent all types of breast cancer. If breast cancer or other problems occur, there is no guarantee that it will be found at an early stage.

Do not become pregnant while taking this medicine or for 2 months after stopping this medicine. Stop taking this medicine if you get pregnant or think you are pregnant and contact your doctor. This medicine may harm your unborn baby. Women who can possibly become pregnant should use birth control methods that do not use hormones during tamoxifen treatment and for 2 months after therapy has stopped. Talk with your health care provider for birth control advice.

Do not breast feed while taking this medicine.

Side effects that you should report to your doctor or health care professional as soon as possible:

• changes in vision (blurred vision)
• changes in your menstrual cycle
• difficulty breathing or shortness of breath
• difficulty walking or talking
• new breast lumps
• numbness
• pelvic pain or pressure
• redness, blistering, peeling or loosening of the skin, including inside the mouth
• skin rash or itching (hives)
• sudden chest pain
• swelling of lips, face, or tongue
• swelling, pain or tenderness in your calf or leg
• unusual bruising or bleeding
• vaginal discharge that is bloody, brown, or rust
• weakness
• yellowing of the whites of the eyes or skin

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

• fatigue
• hair loss, although uncommon and is usually mild
• headache
• hot flashes
• impotence (in men)
• nausea, vomiting (mild)
• vaginal discharge (white or clear)

This list may not describe all possible side effects.

Keep out of the reach of children.

Store at room temperature between 20 and 25 degrees C (68 and 77 degrees F). Protect from light. Keep container tightly closed. Throw away any unused medicine after the expiration date.