There are three different herbs commonly called ginseng: Asian ginseng (Panax ginseng); American ginseng (Panax quinquefolius); and Siberian "ginseng" or eleuthero. Each has different properties and uses. Asian ginseng may be useful for cold and flu prevention, as well as enhancing concentration and memory. American Ginseng may be helpful for lowering type 2 diabetics' blood sugar levels following meals. It is also used as a flavoring in certain soft drinks. Siberian ginseng (eleuthero) is often proposed for stress; and may reduce symptoms of herpes, according to one study.