Our website will soon be relaunched with a fresh look and improved user experience. Take a look by visiting our test site.
Call us 24/7 at (888) 552-6760
Cancer Treatment Centers of America

Tamoxifen (Nolvadex®)


Brand Name: Nolvadex®

Tamoxifen is used in the treatment and prevention of breast cancer.

Tamoxifen is a hormone therapy that belongs to a class of drugs called antiestrogens or selective estrogen receptor modulators. Estrogen is a naturally occurring hormone that sometimes plays a role in the growth of breast cancer cells. Some breast cancer cells contain a protein that attaches to this hormone during its reproduction process.

Breast cancer that relies on estrogen to grow is called “estrogen-receptor positive” or “hormone-sensitive.” Tamoxifen blocks the effects of estrogen on breast cancer cells, thereby stopping the growth of these cells in the body. This drug is effective only for breast cancers that are estrogen-receptor positive. For women who are confirmed to be at high risk of developing breast cancer, tamoxifen may lower the chance of getting this disease.

Tamoxifen is given as a pill that is taken by mouth. Typically, the pill is taken once or twice daily. The exact dose and schedule depends on the type of breast cancer being treated and several other doctors. Your doctor will recommend a regimen tailored to your needs. The medicine should be swallowed with water, and can be taken with or without food.

Tamoxifen side effects

To prevent problematic interactions between tamoxifen and other drugs, be sure to tell your doctor if you are allergic to any medications, and what other medications and supplements you are currently taking. You should also inform your doctor if you have a diabetes, high blood pressure, liver disease, kidney disease, if you are pregnant or planning to become pregnant, or if you are breastfeeding.

Possible side effects from taking tamoxifen may include:

  • Hot flashes
  • Bone pain, joint pain, or tumor pain
  • Swelling in the hands or feet
  • Vaginal itching or dryness
  • Decreased sex drive, impotence, or difficulty having an orgasm
  • Headache or dizziness
  • Depression
  • Thinning hair

Some of tamoxifen’s side effects can be serious. Call your doctor immediately if you experience any of these symptoms:

  • Sudden numbness or weakness, especially on one side of the body
  • Sudden severe headache, confusion, problems with vision, speech or balance
  • Chest pain, sudden cough, wheezing, rapid breathing, fast heart rate
  • Pain, swelling, warmth, or redness in one or both legs
  • Nausea, loss of appetite, increased thirst
  • Muscle weakness
  • Confusion
  • Feeling tired or restless
  • Unusual vaginal bleeding or discharge
  • Irregular menstrual periods
  • Pain or pressure in pelvic area
  • Easy bruising, purple or red pinpoint spots under the skin
  • Fever, chills, aches or other flu-like symptoms
  • New breast lump
  • Upper stomach pain, itching, dark urine, clay-colored stools, jaundice

Please note that this is not a comprehensive list. Patients may experience additional effects not mentioned above.

Tamoxifen may also increase the risk of endometrial cancer and uterine sarcoma, two types of uterine cancer.

At Cancer Treatment Centers of America (CTCA), your team of cancer experts will explain each of the side effects of tamoxifen with you in detail, as well as the side effects and expectations of all other medications planned as part of your individualized treatment plan.

Tamoxifen for cancer treatment

Tamoxifen is approved by the FDA:

  • For the Treatment of metastatic breast cancer
  • As an adjuavant treatment of breast cancer following surgery and/or radiation therapy
  • To reduce the risk of invasive breast cancer for women with ductal carcinoma in situ, to reduce the risk of invasive breast cancer
  • To prevent breast cancer in women known to be at high risk of developing this disease

At Cancer Treatment Centers of America (CTCA), our integrative approach to cancer treatment works to fight your disease on all fronts and ensures that you remain at the center of everything we do. We encourage participation from both you and your family to make certain you are comfortable with all decisions made regarding your treatment.

The information provided here is for educational purposes only. In no way should it be considered as offering medical advice. Cancer Treatment Centers of America assumes no responsibility for how this material is used. Please check with a physician if you suspect you are ill. Also note that while Cancer Treatment Centers of America frequently updates its contents, medical information changes rapidly. Therefore, some information may be out of date.