In a new study they found that certain anti-depressants (Prozac, Paxil or Zoloft) can wipe out the benefits of using tamoxifen:
Breast cancer survivors risk having their disease come back if they use certain antidepressants while also taking the cancer prevention drug tamoxifen, worrisome new research shows.
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About 500,000 women in the United States take tamoxifen, which cuts in half the chances of a breast cancer recurrence. Many of them also take antidepressants for hot flashes, because hormone pills aren’t considered safe after breast cancer.
Breast cancer recurred in about 7 percent of women on tamoxifen alone, and in 14 percent of women also taking other drugs that could interfere — mainly the antidepressants Paxil and Prozac, and, to a lesser extent, Zoloft.