In this session, we will be discussing the consumer medication information for tamoxifen, trade name NolvadexTM.

What it’s for & How to take

Tamoxifen works by decreasing the production of estrogen in your body. Breast cancer tumors usually require estrogen for growth. By blocking the body’s supply of estrogen, the tumor may slow or even reverse in its growth.

Tamoxifen is used to treat breast cancer, in both men and women, which has spread to other parts of the body. This medication may also be used to treat breast cancer following other treatments such as radiation, surgery or chemotherapy. Tamoxifen may be used to reduce the risk of breast cancer in women who are at high risk for the disease due to their age or family medical history. If you are using this medication for a condition other than breast cancer, discuss this with your doctor.

Tamoxifen is usually taken once or twice daily, with or without food, or as directed by your physician. Your specific dosage is based on your clinical condition and response to therapy.

If you forget to take a dose, take it as soon as you remember. If it is near the time of your next dose, skip it and continue with your normal dose time. Do not take a double dose to make up the missed dose.

You may need to take this medication for several years, even if you feel better. Do not decrease your dose or stop taking your medication without talking with your doctor.

While taking tamoxifen, your doctor may have you go to the laboratory for some specific tests such as bone density, cholesterol levels, and liver function tests. These tests are necessary to see how your body is tolerating this medication.

Most Important Warnings

  • Tamoxifen may cause cancer of the uterus, strokes, and blood clots in the lungs. These conditions may be fatal. Tell your doctor if you have ever had a blood clot, you smoke, have high blood pressure, diabetes, if your ability to move around during your waking hours is limited, or if you are taking anticoagulant medications.
  • Call emergency 911 if you have any symptoms of a heart attack such as chest and left arm pain, shortness of breath and sweating or if you have symptoms of a stroke such as weakness on one side of your body, slurred speech, sudden vision changes, and confusion.
  • If you are thinking about taking tamoxifen to reduce the chance of developing breast cancer, talk to your doctor about the risks and benefits of this treatment.

Other Warnings & Cautions

  • Do not take tamoxifen if you are pregnant or breastfeeding. Women of child-bearing age should receive a pregnancy test before beginning therapy with this medication. Both men and women who are using this medication should use two forms of non-hormonal contraception. Discuss with your pharmacist or doctor which is the most reliable, non-estrogen, form of birth control for you to use. If you are taking this medication and think you might be pregnant, contact your doctor immediately.
  • This medication may be absorbed through the skin or into the lungs if the pill dust is inhaled. Because this medication affects the level of estrogen in your body, women who are pregnant or may become pregnant should not handle this medication.
  • If you are taking tamoxifen to treat breast cancer that has spread to other parts of the body, you may experience bone pain after you have started your therapy. This pain may come and go, in short order. Let your physician know if this happens with you
  • This medication may make you dizzy, drowsy, or blur your vision. Do not drive or do any activity that requires focus and attention until you are sure you can do them safely. Limit alcoholic beverages while taking tamoxifen.

Interactions & Side Effects

  • Tell your pharmacist or doctor all your medication allergies so they may determine if tamoxifen is safe for you to take.
  • Avoid dangerous drug interactions. Tell your pharmacist or doctor all the other medication you are taking, including over the counter supplements, even if you don’t take them very often.
  • Ask your doctor if this medication is safe to take with your current health conditions. Tell your doctor if you have liver or kidney disease, high cholesterol, any heart problems or any bone disease such as osteoporosis.
  • While taking tamoxifen, you may feel some hot flashes, hair loss, joint and muscle pain and perhaps some nausea. If these or any other unwanted side effects persist, contact your doctor or pharmacist to talk about it with them.
  • Call your doctor right away if you have any sudden numbness or weakness, severe headache or confusion, swollen glands, or a fractured bone.

If you have any questions about what you have heard, contact your pharmacist or doctor. This session does not include all the potential interactions or side effects that this medication may cause. Ask your pharmacist how your medication should be stored and how you should dispose of it when you are done taking it. Do not share your medication with anyone, ever. Remember, this is not meant to replace your counseling session with your pharmacist. In case of overdose, call your local poison control center at 1-800-222-1222.

Updated 7/20