Ginseng extracts are often used as adaptogen to improve mental performances and well being, helping to overcome stress. Thus, in our times a lot of ginseng extracts are continuously produced and sold into commercial channels. Both Asian and Korean red ginseng (Panax ginseng) and American ginseng (Panax quinquefolius) are the most extensively used and researched.Both Panax ginseng and Panax quinquefolium contain different types of saponins, also known as ginsenosides, which are the substances that give ginseng medicinal properties. Human and animal studies showed that ginseng extracts can also have hypoglycemic effects. The mechanisms by which ginseng reduces blood glucose levels are unclear; some mechanisms have been proposed to explain its hypoglycemic effect, especially modulating effects on insulin sensitization and/or insulin secretion and regulating actions on digestion and intestinal absorption. We describe a case of hypoglycemia by ginseng in type 2 diabetic patient treated with oral hypoglycemic agents. Although, in order to provide better assessments of a sure anti-diabetic efficacy of ginseng, larger and longer randomized controlled clinical trials will be required, in our case we think that we have enough evidence to believe that the cause of hypoglycemia was ginseng. Obviously, this report should not be taken as a proof of the hypoglycemic effect of ginseng, nor it wants to be a suggestion to use ginseng in the treatment of diabetes; instead, it wants to be an alert for patients and clinicians to avoid hypoglycemia in daily clinical practice.