Paxil And Breast Cancer

Every major horror of history
was committed in the name of an altruistic motive.
Ayn Rand
The Fountainhead

Research done by Michelle Cotterchio, M.D., of Cancer Care Ontario found that women who took Paxil saw their risk of breast cancer increase by seven times — even when other possible risk factors were fully accounted for. (Citation: New England Journal of Medicine, Vol. 342, June 29, 2000, p. 2003.)

A second study by Dr. Cotterchio disclosed the fact that Paxil stimulates prolactin secretion and is a potent inhibitor of the cytochrome P450 2D6 enzyme — both factors in an increased breast cancer risk. (Citation: American Journal of Epidemiology, Vol. 151, May 15, 2000, pp. 951-57) The studies included women who had taken Paxil for as few as two weeks.

Dr. Cotterchio and her team of researchers cautioned that the number of women using paroxetine (Paxil) was small and recommended larger trials to confirm their initial finding. (That larger study was performed later, see below.)

A third and subsequent larger study done by another Canadian research team came to the same conclusion as Dr. Cotterchio and her associates. Researchers conducted an investigation among women 35 years or older enrolled in the Saskatchewan Prescription Drug Plan from 1981 to 1995. This group of researchers recommended doctors stop prescribing Paxil (along with four other drugs in the tricyclic class) as a result of their findings. The drugs were classified as “genotoxic” — which means lab experiments have shown they can damage DNA. The researchers also cited the work previously done by Dr. Cotterchio.

The following story Some Depression Drugs Raise Cancer Risk is worth reading; Dr. Cotterchio states that if she took Paxil she would consider switching to another drug because of the magnitude of risk that showed up in the research.

It is unconscionable GlaxoSmithKline targets women suffering from PMDD (Pre Menstrual Dysphoric Disorder) in its Paxil marketing efforts. Even worse perhaps, there is no mention anywhere in Paxil's prescribing information acknowledging the credible scientific link that has now been established between Paxil exposure and breast cancer — not even under the heading of “post-marketing surveillance.”

GSK's "Do More, Feel Better, Live Longer" video
(Windows Media Player or RealOne Player required to view)

Perhaps GlaxoSmithKline should refamilarize itself with Title 21 of the Code of Federal Regulations [section 201.57 (e) Warnings] which states:

[t]he labeling shall be revised to include a warning as soon as there is reasonable evidence of an association of a serious hazard with a drug; a causal relationship need not have been proved.

Three well designed, peer-reviewed medical studies — all of which arrive at the same conclusion — are, by any standard, reasonable evidence of an association of a serious hazard with a drug.

"We take the safety of our medicines extremely seriously...."

Dr. Alastair Benbow
GSK's European Medical Director

That GSK bit is black comedy at its acme, although Benbow's acting ability (click on hyperlink above) is amatuerish at best. A high school drama student could have done a better job delivering those lines. Benbow's feigned sincerity would be laughable were it not such a tragic commentary on the state of affairs at GlaxoSmithKline.

If you, or someone you know, developed breast cancer after taking Paxil, please report it immediately to the United States Food and Drug Administration. This is one way consumer leverage can be applied to GlaxoSmithKline; eventually this official documentation will compel the company to fully disclose the "adverse side effects" of Paxil. You can report your side effects at: MedWatch.