Henbane. Historical illustration of the henbane plant (Hyoscyamus niger) showing the flowers and leaves. This is a poisonous plant which contains the drugs hyoscyamine and scopolamine (hyoscine). Preparations have been used for centuries as a painkiller when applied to arthritic joints. Henbane has also been used as a sedative for patients with nervous disorders. Scopolamine is used in modern medicine to prevent motion sickness. Overdoses of the plant or its preparations may be fatal. From Mathematische und Naturwissenschaften by Johann Geog Heck, 1860.