Amygdalin, also named as ‘laetrile’ and ‘vitamin B17’ was recognized over the years by the followers of natural medicine and has been proposed in research to be having anticancer effects.1 It is one of the most controversial vitamins in the last three decades. It is a cyanogenic plant glucoside belonging to the Rosaceae family found in the pits of numerous fruits, raw nuts as apricot stones, almonds, cherries, peaches and plums. It is also found in plants, such as lima beans, clover, and sorghum.2 Laetrile word is derived from the terms levorotatory and mandelonitrile.1,3 Laevorotary describes stereochemistry while mandelonitrile refers to its chemical identity. Amygdalin has chemical formula C20H10NO11 and molecular weight is supposed to be 457.42 Dalton. It was used to treat asthma, bronchitis, leprosy and leukoderma in ancient period.1 Amygdalin produces HCN which is poisonous and is decomposed by enzymes. The various pharmacological effects of laetrile include antiatherogenic, activity in renal fibrosis, pulmonary inflammatory activities. Laetrile has been manufactured and used by over 20 countries like Japan, China, America and Italy for cure of cancer as an alternative medicine. In recent years, anti-cancerous effect of amygdalin has become an upcoming and controversial topic. Though it was encouraged for cure of cancer due to lack of sufficient clinical trials and some adverse cyanogenic effects it was not promoted by FDA fully for cancer therapy.
Amygdalin is a widely sourced natural product that has shown antitumor activity and is comparatively low priced, it might come up as a future antitumour drug with synergistic effects. A number of studies have shown that amygdalin has a contributory role in the treatment of diabetes, cancer, immunosuppression and atherosclerosis. Randomized controlled clinical trials should establish the efficacy of laetrile along with standardization of acceptable formulations, dosage and the methods of administration. Both cell line studies and human trials should be carried out to explore other benefits of laetrile and to promote the product as nutritional supplement. The pharmacological activity of amygdalin is clear, but more systematic indepth research is needed with well - designed controlled clinical trials to be approved for human use.