Drug Interactions Newsletter

Volume 2, Issue 34, 09/07/2010

Question

What is the mechanism by which tamoxifen's (Nolvadex) efficacy in treating breast cancer is decreased by the use of paroxetine (Paxil)?

Answer

Tamoxifen (Nolvadex) is a selective estrogen receptor modulator (SERM) that is effective and approved for the treatment of breast cancer in both males and females.(1)  Unfortunately, one of the troublesome side effects with tamoxifen is the development of hot flashes.(2)  Since stopping tamoxifen is not always a desirable option in patients with breast cancer, the treatment of the hot flashes has been successfully managed by...