Withania somnifera, known commonly as ashwagandha, Indian ginseng, poison gooseberry, or winter cherry, is a plant in the solanaceae or nightshade family. Several other species in the genus Withania are morphologically similar. It is used as a herb in Ayurvedic medicine.

Bioactive constituent withaferin A has shown potential in therapy for glioblastomas, although this is not a traditional use of the plant. The plant's long, brown, tuberous roots are used in traditional medicine. In Ayurveda, the berries and leaves are applied externally to tumors, tubercular glands, carbuncles, and ulcers. The roots are used to prepare the herbal remedy ashwagandha. The traditional use is as a powder, mixed with warm milk and honey, and taken before bed. In Yemen, where it is known as ubab, the dried leaves are ground to a powder from which a paste is made and used in the treatment of burns and wounds.

Ashwagandha root extract is a popular supplement, with purported benefits including reduction of anxiety and stress. The extract is also thought to reduce total cholesterol levels, increase power output and muscle mass and has other, less significant effects.