Laetrile is a drug used to treat cancer. It is considered an alternative medicine, primarily used in Mexico, according to WebMD. It is not approved for use in the United States.
Laetrile is a form of the chemical amygdalin, found in the pits of many fruits and nuts. Cyanide is believed to be the main anticancer component in laetrile, states WebMD.
Laetrile was first used to treat cancer in Russia in 1945. In the 1970s, laetrile became popular in the United States as a new and promising cancer therapy. It was legalized in 20 states. The U.S. Supreme Court banned the use of laetrile in 1980, after scientific studies found little evidence to support it as an anticancer treatment in animals and no evidence of its effectiveness in treating humans, reports WebMD.
American actor Steve McQueen claimed he was recovering from lung cancer after getting laetrile treatments in Mexico in July 1980, reports the New York Times. However, he died four months later. While many anecdotal reports about laetrile exist, only two clinical trials on humans have been published, according to WebMD. The studies found no evidence that laetrile had a positive effect.
Laetrile has serious side effects, similar to cyanide poisoning, states WebMD. They include nausea, vomiting, headache, dizziness and low blood pressure.