Paris, February 09: A common antidepressant weakens or cancels the beneficial effects of a standard treatment for breast cancer, according to a study released today.
Women who take the mood drug paroxetine – better known by its brand names Paxil and Seroxat – at the same time as the breast cancer medication tamoxifen face an increased risk of death, researchers reported.
The antidepressant alone has no impact on the course of the disease but should not be taken at the same time as anti- cancer drug, the study recommended.
Tamoxifen significantly improves survival for the dominant type of breast cancer, the most commonly diagnosed cancer in women worldwide. But to work properly, it must be converted by the liver into an active metabolite, the chemical that remains after a drug is broken down by the body.
It was previously suspected that antidepressants that boost the release of the naturally occurring neurotransmitter serotonin, such as paroxetine, might interfere with this process.
To find out, Catherine Kelly and colleagues at the Institute for Clinical Evaluative Sciences in Toronto, Canada investigated the health care records of 2,430 women with breast cancer who had received tamoxifen from 1993 to 2005.
About 30 per cent of these women also received an anti depressant – paroxetine more than any other – at the same time often prescribed over long periods to help patients cope with the stress of battling the deadly disease.
—PTI