Ginsengs: A Review of Safety and Efficacy

Both Korean and Siberian ginseng are used extensively for the enhancement of mental and physical performance. However, results from recent randomized, controlled clinical trials do not substantiate the purported ergogenic effects of ginseng in healthy individuals. Nevertheless, there is some evidence (both human and animal studies) to suggest that Korean and Siberian ginseng may have health promoting effects by stimulating the immune response. The recommended daily dose for Korean ginseng is 0.5 to 2 g per day of dried root or 100 to 300 mg per day of a standardized extract containing 1.5 to 7% ginsenosides and, for Siberian ginseng, 2 to 3 g per day of dried root or equivalent preparations. Patients should be cautioned not to exceed these dosages, as adverse reactions such as hypertension, diarrhea, nervousness, and insomnia are associated with excessive ingestion. For Korean ginseng, drug interactions have been reported with both phenelzine and warfarin. There is a single case report of an interaction between Siberian ginseng and digoxin; however, the clinical significance has not been established. The use of ginseng is contraindicated for children and women who are pregnant or lactating, while Siberian ginseng should also be avoided by those patients with cardiovascular disease or hypertension (BP>180/90 mmHg).