Published studies of the weight loss drug orlistat (Xenical and Alii) under-reported adverse events 3- to 33-fold compared to the number of investigator-reported adverse events even though six of seven papers stated that “all adverse events were recorded” according to an analysis of orlistat studies by Prof. Peter Gotzsche, MD and others from the Cochrane Collaboration.

Do you believe that this is also true for studies of cholesterol drugs (statins) and blood pressure drugs and diabetes drugs and antidepressants and anti-anxiety drugs and sleeping pills and bone-building drugs and acid-blocking drugs and every other drug out there?

Yes, of course it is.

I believe that drug-induced side effects are dramatically underreported in all drug studies sponsored by the drug companies.

This is just one example of this.

“For one trial [of the weight loss drug orlistat (Xenical, Alii)], we identified an additional 1,318 adverse events that were not listed or mentioned in the [clinical study reports] itself [or the published paper] but could be identified through manually counting individual adverse events reported in an appendix, ” according to an analysis of orlistat studies by Prof. Peter Gotzsche, MD and others from the Cochrane Collaboration.

“We discovered that the majority of patients [given the weight loss drug orlistat (Xenical, Alii)] had multiple episodes of the same adverse event that were only counted once, though this was not described in the [clinical study reports] [or the published paper],” according to an analysis of orlistat studies by Prof. Peter Gotzsche, MD and others from the Cochrane Collaboration.

“We also discovered that participants treated with orlistat experienced twice as many days with adverse events as participants treated with placebo… Furthermore, compared with the placebo group, adverse events in the orlistat group were more severe... [however] None of this was stated in the [clinical study reports] or in the published paper,” according to an analysis of orlistat studies by Prof. Peter Gotzsche, MD and others from the Cochrane Collaboration.

Orlistat, which is the active ingredient found in the weight loss drugs Xenical and Alli, inhibits a key enzyme, increases toxicity of the liver and kidneys, and reduces effectiveness of some anti-cancer drugs according to a study by Professor Bingfang Yan which was funded by the U.S. National Institutes of Health.

Yan notes that this inhibition occurs with a low level of the drug.

He also notes that “Since it has been available over–the-counter, there has been a drastic increase of toxicity among patients using the drug,” Yan said.

“It has been linked to severe liver failure, acute pancreatic failure and acute renal (kidney) failure.”