In a new study, tamoxifen citrate (Nolvadex drags, AstraZeneca), best known as a treatment for breast cancer, dramatically reduced symptoms of the manic phase of bipolar disorder more quickly than many standard medications for the mental illness. By the end of the study, 63% of the patients taking tamoxifen had reduced manic symptoms, compared with only 13% of those taking a placebo. Patients taking tamoxifen responded by the fifth day.
Researchers at the National Institute of Mental Health (NIMH) explained that generic tamoxifen blocks an enzyme called protein kinase C (PKC), which regulates activiti es in brain cells. The enzyme is thought to be overactive during the manic phase of bipolar disorder.
By pointing to PKC as a target for new drugs, the study raises the possibility of developing faster-acting treatments for the manic phase of the illness. Current medications for the manic phase generally take more than a week to begin working.
However, it is not clear whether (buy) tamoxifen will become a treatment of choice; it blocks estrogen, which makes it useful as a treatment for breast cancer—but it may cause endometrial cancer if it is taken over long periods of time.