Weight Loss Drug May Cause Irreversible Damage

Taking shortcuts in the war against obesity can cost us dearly. Popular weight loss drug orlistat, known as Alli, has been approved by the FDA in 1999 and has been available over the counter since 2007. The new study by a researcher from the University of Rhode Island shows that Alli can cause severe toxicity of kidneys and liver and can interfere with the efficacy of other drugs.

How does Alli work?

Professor Binghang Yan, who investigated the effects of orlistat has discovered that orlistat affects the production of an important enzyme, potentially causing dangerous levels of toxicity of liver, kidneys and other internal organs. The damage is irreversible and even a low level of the drug is enough to cause it.

Orlistat prevents body from absorbing fat and it has been advertised as safe, since it does not get absorbed by the system. But, Professor Yan found that in fact orlistat is absorbed by internal organs, particularly liver and kidneys.

According to the study findings, the drug is a powerful inhibitor of carboxylesterase-2, a major enzyme that causes detoxification of the kidneys, liver, kidney and digestive tract.

Interaction with other drugs

In addition, the study found that orlistat affects metabolism of a range of drugs, such as aspirin and the cancer fighting drugs pentyl carbamate of p-aminobenzyl carbamate of doxazolidine and irinotecan. Orlistat not only limits the effectiveness of cancer drugs, but it actually boosts the proliferation of cancer cells.

In case of aspirin, used as a blood thinner, orlistat increases its effectiveness, causing potential bleeding.

Yan alerted the U.S. Food and Drug Administration of the results of his study. FDA has recently approved several anti-obesity drugs, in spite of serious opposition, due to the potential side effects, as well as effects on public campaigns for changing the lifestyle, as the only safe way to lose weight and keep it off.


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