Panax Ginseng root extract, side effects, safety, by Ray Sahelian, M.D. Health benefit

The root of the panax ginseng plant has been used in China, Japan, and Korea for many centuries for enhancing vitality. There are several varieties of ginseng sold over the counter: Asian ginseng ( Panax ginseng ), American Ginseng ( Panax quinquefolius ), and Siberian ginseng ( Eleutherococcus Chinensis ) are the most common. Hundreds of ginseng products are available over the counter with different dosages and combinations.

Panax ginseng and blood sugar
Single doses of this traditional herbal treatment have been shown to lower blood glucose levels and elicit cognitive improvements in healthy volunteers. The specific mechanisms responsible for these effects are not known. However, cognitive improvements may be related to the glycemic properties of panax ginseng. Those with diabetes who plan to take it for prolonged periods should use low dosages since one side effect of high dose use is insomnia.

The glycemic effects of single doses of Panax ginseng in young healthy volunteers.
Br J Nutr. 2006. Human Cognitive Neuroscience Unit, Division of Psychology, Northumbria University, Newcastle upon Tyne, UK.
The results of two acute placebo-controlled, double-blind cross-over studies assessing the effect of Panax ginseng (G115) on blood glucose levels are reported. In study 1, thirty participants received three treatments: placebo; 200 mg G115; 400 mg G115. In study 2, twenty-seven participants received four treatments: placebo (0 mg ginseng and 30 mg saccharin); ginseng (200 mg ginseng and 30 mg saccharin); placebo-glucose (0 mg ginseng and 25 g oral glucose); ginseng-glucose (200 mg ginseng and 25 g oral glucose). Blood glucose levels were measured at baseline (at 09.00 hours after an overnight fast) and then 60, 90 (study 1 only) and 120 min post-dose. Both studies demonstrated that G115 alone significantly lowers fasting blood glucose levels. Conversely, in study 2 there was a significant drink x ginseng interaction suggesting opposing glycemic effects of ginseng under fasting and raised blood glucose conditions.

Interactions with medications
Imatinib and Panax ginseng: A Potential Interaction Resulting in Liver Toxicity.
Ann Pharmacother. 2010. Division of Internal Medicine, Medical College of Wisconsin, Milwaukee, WI.
To report a case of imatinib-induced hepatotoxicity after concurrent ginseng ingestion in a patient with chronic myelogenous leukemia (CML). A 26-year-old man with CML who had taken imatinib 400 mg daily for 7 years with no complications presented with right upper quadrant pain. Laboratory test results included alanine aminotransferase 1069 U/L, aspartate aminotransferase 481 U/L, alkaline phosphatase 124 IU/L, total bilirubin 1.4 mg/dL, albumin 4.0 g/dL, and international normalized ratio 1.08. Liver biopsy showed acute lobular hepatitis favoring a drug-induced etiology, and a diagnosis of imatinib-induced hepatotoxicity was made. The patient's only lifestyle modification prior to the diagnosis of liver toxicity was daily ingestion of Panax ginseng via energy drinks for the past 3 months. Both imatinib and ginseng were discontinued, and the patient was treated with a short course of corticosteroids. Imatinib was later restarted at the same dose with no recurrent elevations in his liver enzyme levels. Imatinib-associated hepatotoxicity usually presents within 1-2 years of therapy initiation, with the median time to hepatotoxicity being 100 days. Ginseng is an herb that is not known to be hepatotoxic. In vivo, ginseng is known to inhibit CYP3A4, the primary enzyme involved in the metabolism of imatinib. We propose that our patient's late-onset imatinib-associated hepatotoxicity was due to an interaction between ginseng and imatinib through CYP3A4. Based on the Naranjo probability scale, it is probable that imatinib caused this patient's liver toxicity, and the Horn drug interaction probability scale also indicates a probable interaction between imatinib and ginseng. This case emphasizes the importance of continuous monitoring of liver function tests even after several years of imatinib therapy and the importance of advising patients to avoid ginseng and any other over-the-counter herbal supplements that may interact with imatinib.