Related Terms

• Amygdalin, Armeniaca vulgaris, apricock, apricot kernel, apricot kernel oil, apricot oil, apricot pits, apricot seed, benzaldehyde, cyanophoric glycosides, hydrocyanic acid, ku xing ren (Chinese), Laetrile®, mandelonitrile, mandelonitrile beta-D-gentiobioside, mandelonitrile-beta-glucuronide, prunasin, Prunus (genus), semen Pruni armeniacae, vitamin B17, xìng rén (Chinese).

Background

• Nitriloside is a generic term for beta-cyanophoric glycosides, a large group of water-soluble, sugar-containing compounds found in a number of plants. Amygdalin (also called laetrile), is one of the most common nitrilosides. Amygdalin is found in the seeds of many fruits, particularly apricots, as well as in grains and grasses.

• A patented form of the compound, also called Laetrile®, is a partly man-made molecule and shares only part of the amygdalin structure. Both Laetrile® and amygdalin have been promoted and sold as "vitamin B-17", although neither compound is a vitamin.

• Chinese medicine practitioners have used apricot seed as a treatment for respiratory diseases, including bronchitis and emphysema. It is believed to suppress coughs and to help remove mucus. The oil has also been used as a laxative. Small amounts are said to stimulate breathing, improve digestion, and give a sense of well-being. It has also been used to treat rheumatic disease in Germany and high blood pressure in both Germany and the United States.

• Laetrile® has been used as a cancer treatment. It was first used for this purpose in Russia in 1845 and later in the United States and Mexico. More recently, the American Cancer Society (ACS) has stated that the use of Laetrile® or amygdalin to treat cancer is not supported by the available scientific evidence. The ACS warns that these compounds may be converted to cyanide in the body. A number of cases of cyanide poisoning associated with Laetrile® have been reported. The National Institutes of Health (NIH) has similarly reported that clinical evidence has shown laetrile to be of little benefit against cancer and that its side effects resemble those of cyanide poisoning.

• Laetrile® and amygdalin are not approved by the U.S. Food and Drug Administration (FDA) as a treatment for cancer.

Scientific Evidence

Tradition/Theory

The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious and should be evaluated by a qualified health care professional.

• Anthelmintic (kills intestinal/parasitic worms), antiseptic, arthritis, asthma, bronchitis (acute or chronic), constipation, cough, emphysema, expectorant (encourages coughing up of mucus), eye inflammation, hemorrhage, high blood pressure, infertility, muscle or intestinal spasms, pain relief, rheumatic diseases (joint and muscle diseases), sedative, skin care, vaginal infections, vitamin deficiencies, wound healing.

Dosing

The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

Adults (18 years and older)

• There is no proven safe or effective dose for nitrilosides in adults. Nitrilosides have been taken by mouth as amygdalin/laetrile, Laetrile®, apricot kernel, or apricot seed. Nitrilosides have been injected intravenously as amygdalin. Laetrile® and amygdalin are not approved by the U.S. Food and Drug Administration (FDA) as a treatment for cancer. Cyanide toxicity is a major concern.

Children (under 18 years old)

• There is no proven safe or effective dose for nitrilosides in children. Laetrile® and amygdalin are not approved by the U.S. Food and Drug Administration (FDA) as a treatment for cancer. Cyanide toxicity is a major concern.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

• Avoid with known allergy or hypersensitivity to nitrilosides, Laetrile®, or laetrile/amygdalin. Hives have been observed in individuals using these compounds.

Side Effects and Warnings

• Laetrile® and amygdalin are not approved by the U.S. Food and Drug Administration (FDA) as a treatment for cancer. Moreover, the American Cancer Society (ACS) has stated that claims that these compounds are effective cancer treatments are not supported by the available scientific evidence. ACS also warns that these compounds may be converted to cyanide in the body and that a number of cases of cyanide poisoning associated with Laetrile® have been reported. The National Institutes of Health (NIH) has similarly reported that clinical evidence has shown laetrile to be of little benefit against cancer and that side effects resemble those of cyanide poisoning.

• Nitrilosides may cause "body shaking", breathing problems (shortness of breath, violent breathing), breath odor (like peach blossoms or bitter almond), chest pain, diarrhea, goiter, increased appetite, increased weight, low pulse, thyroid cancer, or tightness in the throat or chest. Symptoms of severe cyanide poisoning or apricot kernel poisoning may include abdominal pain, bizarre behavior, blindness, coma, cyanosis (bluish color of the skin and the mucous membranes due to insufficient oxygen in the blood), death, dilated pupils, dizziness, fever, glassy or protruding eyes, headache, hives, increased blood cyanide levels, itchy or swollen skin, light-headedness, liver damage, low blood pressure, mental confusion, nausea, nerve damage, rapid heartbeat, rash, respiratory failure, seizures, sleepiness, trembling, vomiting, and weakness.

• Use cautiously when taking by mouth, due to the possibility of cyanide poisoning. Amygdalin taken together with beta-glucosidase may increase the risk of cyanide poisoning.

• Nitrilosides may cause low blood pressure. Caution is advised in patients taking drugs, herbs or supplements that lower blood pressure.

• Use cautiously in patients with abnormal heart rhythms, due to reports of rapid heartbeat with amygdalin use.

• Use cautiously in patients taking vitamin C or those consuming foods rich in vitamin C, as vitamin C has been shown to increase conversion of amygdalin to cyanide and to reduce body stores of cysteine, which is used to detoxify cyanide.

• Avoid in women who are pregnant or breastfeeding, due to a lack of safety data and due to warnings from the American Cancer Society and National Institutes of Health of possible cyanide poisoning linked to amygdalin use.

• Avoid in patients with a known allergy/hypersensitivity to nitrilosides, Laetrile®, or laetrile/amygdalin.

Pregnancy and Breastfeeding

• Avoid in women who are pregnant or breastfeeding, due to a lack of safety data and due to warnings from the American Cancer Society (ACS) and National Institutes of Health (NIH) of possible cyanide poisoning linked to amygdalin use.

Interactions

Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.

Interactions with Drugs

• Nitrilosides may cause low blood pressure. Caution is advised in patients taking drugs that lower blood pressure.

• Nitrilosides may also interact with antiarrhythmic agents (medications that treat irregular heartbeat).

Interactions with Herbs and Dietary Supplements

• Nitrilosides may cause low blood pressure. Caution is advised in patients taking herbs or supplements that lower blood pressure.

• Nitrilosides may also interact with antiarrhythmic herbs and supplements (agents that treat irregular heartbeat), beta-glucosidase-containing foods, vitamin C, and vitamin C-containing foods.

Author Information

• This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

References

Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to www.naturalstandard.com. Selected references are listed below.

1. Bromley J, Hughes BG, Leong DC, et al. Life-threatening interaction between complementary medicines: cyanide toxicity following ingestion of amygdalin and vitamin C. Ann Pharmacother 2005;39(9):1566-1569. View Abstract

2. Davignon JP, Trissel LA, Kleinman LM. Pharmaceutical assessment of amygdalin (Laetrile) products. Cancer Treat Rep 1978;62(1):99-104. View Abstract

3. Greenberg DM. The case against laetrile: the fraudulent cancer remedy. Cancer 1980;45(4):799-807. View Abstract

4. Milazzo S, Ernst E, Lejeune S, et al. Laetrile treatment for cancer. Cochrane Database Syst Rev 2006;(2):CD005476. View Abstract

5. Milazzo S, Lejeune S, Ernst E. Laetrile for cancer: a systematic review of the clinical evidence. Support Care Cancer 2007;15(6):583-595. View Abstract

6. Moertel CG, Ames MM, Kovach JS, et al. A pharmacologic and toxicological study of amygdalin. JAMA 1981;245(6):591-594. View Abstract

7. Moertel CG, Fleming TR, Rubin J, et al. A clinical trial of amygdalin (Laetrile) in the treatment of human cancer. N Engl J Med 1982;306(4):201-206. View Abstract

8. No authors listed. Unproven methods of cancer management. Laetrile. CA Cancer J Clin 1991;41(3):187-192. View Abstract

9. Osterberg S. [Dangerous to eat: apricot seed preparation]. Lakartidningen 1978;75(39):3438. View Abstract

10. Rauws AG, Olling M, Timmerman A. The pharmacokinetics of amygdalin. Arch Toxicol 1982;49(3-4):311-319. View Abstract

11. Rauws AG, Olling M, Timmerman A. The pharmacokinetics of prunasin, a metabolite of amygdalin. J Toxicol Clin Toxicol 1982;19(8):851-856. View Abstract

12. Rubino MJ, Davidoff F. Cyanide poisoning from apricot seeds. JAMA 1979;241(4):359. View Abstract

13. Sadoff L, Fuchs K, Hollander J. Rapid death associated with laetrile ingestion. JAMA 1978;239(15):1532. View Abstract

14. Suchard JR, Wallace KL, Gerkin RD. Acute cyanide toxicity caused by apricot kernel ingestion. Ann Emerg Med 1998;32(6):742-744. View Abstract

15. Tlirnoveanu C, Popescu E, Negulescu I, et al. [Study of acute poisonings with cyanogenetic substances (apricot seed kernels)]. Rev Pediatr Obstet Ginecol Pediatr 1982;31(3):249-252. View Abstract