Safety alert for breast cancer patients on antidepressants

THE TGA advises caution over prescribing tamoxifen plus the selective serotonin reuptake inhibitor (SSRI) paroxetine in women with breast cancer.

A safety alert on the drug interaction was issued after an observational study found an association between concurrent use of tamoxifen and paroxetine and an increased risk of breast cancer mortality.

The clinical effect has been attributed to reduced conversion by cytochrome P450 2D6 (CYP2D6) of tamoxifen to a major active metabolite.

Although evidence from epidemiological studies was conflicting, the mechanism of the effect was  biologically plausible, the