February 12, 20108:23 am
posted by Aric Thorpe, MHR
Tamoxifen and paroxetine combination increases mortality in breast cancer patients
Breast cancer patients taking the drug tamoxifen and the drug paroxetine (Paxil) concurrently may have an increased risk for breast cancer mortality. An accumulation of findings from previous studies indicate that paroxetine may cause a inhibition of cytochrome P450 2D6 isozyme (CYP2D6) in patients taking tamoxifen; now findings reported online in BMJ indicate that patients who have used the drugs together may have a excess breast cancer mortality risk up to 91%, although this varies by the duration of concurrent use. According to David Juurlink, MD, PhD, of Sunnybrook Health Sciences Center in Toronto, and colleagues, “… the use of paroxetine for 41% of tamoxifen treatment (the median overlap in our sample) would result in one additional breast cancer death within five years of cessation of tamoxifen for every 19.7 patients so treated; the risk with more extensive overlap would be greater.” Click here to read an article from Business Week that discusses this study more.
