Unlike prescription and over-the-counter pharmaceuticals, dietary supplements do not require FDA approval and do not undergo the same premarketing evaluation of safety and efficacy as drugs, and purveyors may or may not adhere to good manufacturing practices and quality control standards. Supplements may cause illness as a result of intrinsic toxicity, misidentification or mislabeling, drug-herb reactions, or intentional adulteration with pharmaceuticals. If you suspect a dietary supplement or herbal product may be the cause of an otherwise unexplained illness, contact the FDA (1-888-463-6332) or the regional poison control center (1-800-222-1222), or consult the following online database: https://www.fda.gov/food/dietary-supplements.
Table 38–7 lists selected examples of clinical toxicity from some of these products.
Table 38–7.Examples of potential toxicity associated with some dietary supplements and herbal medicines (listed in alphabetical order). ||Download (.pdf) Table 38–7. Examples of potential toxicity associated with some dietary supplements and herbal medicines (listed in alphabetical order).
|Product ||Common Use ||Possible Toxicity |
|Azarcon (Greta) ||Mexican folk remedy for abdominal pain, colic ||Contains lead |
|Comfrey ||Gastric upset, diarrhea ||Contains pyrrolizidine alkaloids, can cause hepatic veno-occlusive disease |
|Creatine ||Athletic performance enhancement ||Nausea, diarrhea, abdominal cramps; elevated serum creatinine |
|Ginkgo ||Memory improvement, tinnitus ||Antiplatelet effects, hemorrhage; abdominal pain, diarrhea |
|Ginseng ||Immune system; stress ||Decreased glucose; increased cortisol |
|Guarana ||Athletic performance enhancement, appetite suppression ||Contains caffeine: can cause tremor, tachycardia, vomiting |
|Kava ||Anxiety, insomnia ||Drowsiness, hepatitis, skin rash |
|Ma huang ||Stimulant; athletic performance enhancement ||Contains ephedrine: anxiety, insomnia, hypertension, tachycardia, seizures |
|Spirulina ||Body building ||Niacin-like flushing reaction |
|Yohimbine ||Sexual enhancement ||Hallucinations, hypertension, tachycardia |
|Zinc ||Cold/flu symptoms ||Nausea, oral irritation, anosmia |
et al. Toxicity of herbs, vitamins and supplements. Adv Chronic Kidney Dis. 2020;27:67.
et al. Collective exposure to lead from an approved natural product-derived drug in Korea. Ann Occup Environ Med. 2019;31:e20.
et al. Botanicals and hepatotoxicity. Clin Pharmacol Ther. 2018;104:458.