Withania somnifera, known commonly as ashwagandha,[2][3][4] is an evergreen shrub in the Solanaceae or nightshade family that grows in Nepal, India, the Middle East, and parts of Africa.

[4] Its use in herbal medicine and dietary supplements notwithstanding, scientific evidence is insufficient to show that W. somnifera is safe or effective for treating any health condition or disease.

[11] A treehopper (Oxyrachis tarandus) feeds on the apical portions of the stem, making them rough and woody in appearance and brown in colour.

[3] Limited clinical studies have found that supplementation with various ashwagandha extracts may decrease anxiety and perceived stress, and improve sleep.

[3][4][16] As the studies used different extract preparations, durations of use, doses, and types of subjects, how ashwagandha may have effects in people remains undetermined, as of 2023.

[3][4][17] The most common side effects include diarrhea, headache, sedation, or nausea, and the product should not be used during pregnancy or breastfeeding.