Vitamin B17 is not a B vitamin and is also known as bitter amygdalin, which has been shown in studies to have cough suppressant, anti-inflammatory, anti-tumor, and anti-coagulant effects, some of which are controversial. Bitter amygdalin is a widely used substance in the field of medicine and food, with important physiological activity and pharmacological value. A large number of experiments have shown that bitter amygdalin has the efficacy of expectorant and cough suppressant. Amygdalin will be decomposed in the stomach, and the hydrocyanic acid it produces can inhibit the respiratory center so as to achieve the effect of cough, but hydrocyanic acid is poisonous, and it is easy to be poisoned by taking a large amount of amygdalin orally. Experiments show that amygdalin has excellent anti-inflammatory effect, in addition, it has a certain inhibitory effect on the proliferation and spread of cancer cells, the study of the anti-cancer effect of amygdalin has been in progress, at present, for bladder cancer, hepatocellular carcinoma and so on show good therapeutic effect, but its mechanism of action and dosage research lack of clinical significance. Experiments have proved that bitter amygdalin also has good efficacy in regulating immunity and treating hepatocellular fibrosis, etc., but the research lacks the effect of its toxic side effects on the organism, the study of its transformation in the body, and the lack of clinical trials. Whether it can work better and get produced or used clinically is still to be decided by research. Because the efficacy and effect of bitter amygdalin still need to be further studied, because of its toxic side effects, so do not blindly buy and use. If you need to use amygdalin preparations, you must consult your doctor before using them and follow his or her instructions.