Tamoxifen breast cancer medication by Ray Sahelian, M.D. Tamoxifen side effects

Tamoxifen was sold by AstraZeneca Plc under the name Nolvadex but is now marketed by several generic drug makers. It remains the only drug approved for use in preventing breast cancer in women who have not yet reached menopause. Questions have been raised on the benefit versus risk profile for the use of tamoxifen in women with low to moderate risk of breast cancer recurrence. See the link for natural options in prevention or treatment of breast cancer.

   Tamoxifen is a medication in pill form that interferes with the activity of estrogen (a hormone). Tamoxifen has been used for more than 20 years to treat patients with advanced breast cancer. It is used as adjuvant, or additional, therapy following primary treatment for early stage breast cancer. In women at very high risk of developing breast cancer, tamoxifen may reduce the chance of developing the disease. Tamoxifen continues to be studied for the prevention of breast cancer. It is also being studied in the treatment of several other types of cancer. It is important to note that tamoxifen is also used to treat men with breast cancer.

Is Tamoxifen that helpful?
Tamoxifen, the pill that prevents breast cancer in high-risk women, does not appear in the long run to save many lives. Women at the highest risk of breast cancer do appear to live longer if they take tamoxifen. But for women at the low end of the high-risk group, the sometimes serious side effects of tamoxifen outweigh the benefits. Tamoxifen can cause blood clots and uterine cancer. Melnikow and her colleagues calculated that tamoxifen can extend life expectancy only when a woman's five-year risk of developing breast cancer is 3 percent or higher. This is especially true for women who have not had a hysterectomy, and thus risk endometrial cancer from taking tamoxifen. Many women are in any case switching to a newer class of drugs known as aromatase inhibitors to treat breast cancer or to the osteoporosis drug raloxifene to prevent it. Raloxifene, made by Eli Lilly and Co. under the name Evista, has been shown to prevent breast cancer as well as tamoxifen does, without causing as many blood clots, cataracts or as many cases of uterine cancer. Researchers report that women with breast cancer who switched to Pfizer Inc.'s drug Aromasin after taking tamoxifen were 17 percent less likely to die. In women considered at high risk of breast cancer, usually meaning they have a close relative with breast cancer, have had several suspicious-looking lumps, or other conditions, tamoxifen reduced their risk of breast cancer by 49 percent. Cancer, July 24, 2006.

How does Tamoxifen work?
Tamoxifen is prescribed to treat early and advanced stages of breast cancer and prevent breast cancer recurrence. Tamoxifen blocks estrogen, which can help fuel the growth of tumors in some cases.

Tamoxifen side effects
The most common tamoxifen side effects are hot flashes and other menopausal symptoms, vaginal dryness, nausea, low libido, and mood swings. Other tamoxifen side effects reported include headache and menstrual changes.

Tamoxifen Alternative

Aromasin, known generically as exemestane, and similar drugs inhibit the enzyme aromatase, which is needed to produce estrogen. The aromatase inhibitors are now being used just after breast cancer surgery instead of tamoxifen in many women to keep the disease from returning.