About Laetrile Or Vitamin B-16

Laetrile has had its ups and downs as an alternative medicine. Created from amydalin, a substance found in fruit pits and sold as an alternative anti-cancer drug by Ernest Krebs, Sr. and his son from the 1950s through the 1970s, laetrile has never proven its claims. Called B-17 even though it's not a vitamin, laetrile made from apricot pits sold in Mexico differs from a partially synthetic form of amygdalin sold in the United States as laetrile. Laetrile can have dangerous side effects, since fruit pits contain cyanide.

Different Types of Laetrile

The term "laetrile" is used interchangeably to refer to three different substances. Amygdalin, a natural substance found in large amounts in apricot and peach pits, is the source of laetrile sold as an alternative cancer treatment in a number of clinics in Mexico. Laetrile is also the commercial name of a semi-synthetic medication made from amygdalin.

Why It's Called B-17

Ernest Krebs Jr. coined the term B-17 for laetrile, although laetrile doesn't fit the description of a vitamin, since it's not essential for life. His motives may have been to give the drug respectability or to avoid United States Food and Drug Administration interference with its sales by labeling it a supplement rather than a drug.

Historical Use

Russian scientists used amygdalin as a cancer treatment as early as 1985, but its potentially life threatening toxicity caused by its cyanide content made it unpopular. Ernest Krebs, Sr. created and sold his purified laetrile starting in the 1950s. As many as 70,000 Americans took laetrile by 1978, according to the National Cancer Institute, many in Mexican clinics set up to avoid U.S. drug regulations.

Effectiveness

No studies have shown any benefit in treating cancer with laetrile. A British review of literature conducted by the Institute of Health and Social Care and reported in the June 2007 issue of "Supportive Care in Cancer" examined 36 reports on the use of laetrile in cancer treatment. None were controlled clinical trials. None of the studies showed positive results in patients taking laetrile as a cancer treatment.

Risks

Laetrile causes side effects similar to cyanide poisoning, including nausea, vomiting, low blood pressure, mental confusion, liver damage, headaches, nerve damage and, in some cases, coma and death. Taking laetrile orally increases the risk of side effects compared to taking it by injection, according to the National Cancer Institute. Taking large amounts of vitamin C at the same time also increases the risk of severe side effects.