Ashwagandha

Withania somnifera · Winter Cherry · Indian Ginseng

Snapshot

Indications	Contraindications
Stress¹ Anxiety symptoms^1–8 Insomnia and sleep quality⁹ Fatigue^{10, 11} Cardiorespiratory endurance¹² Male fertility¹³	Pregnancy or breastfeeding¹³ Hormone-sensitive prostate cancer¹³ Autoimmune or thyroid disorders¹³ Upcoming surgery¹³

Ashwagandha (Withania somnifera) is an evergreen shrub that has been used in Ayurvedic medicine for thousands of years¹³. Its main draw is a dampened stress response, probably via the hypothalamic-pituitary-adrenal (HPA) axis and cortisol¹⁴. Adults with high stress use it mainly for stress and anxiety, then for sleep and insomnia. Fatigue, male fertility and testosterone, and athletic performance are also pursued, with limited evidence¹³.

Meta-analyses of randomized trials found lower stress and anxiety scores^{1, 3}, and one rated the certainty of that evidence low. A National Institutes of Health (NIH) fact sheet calls the anxiety evidence unclear¹³. Sleep effects were small but significant, and larger in adults with insomnia⁹. A 2023 case report described jaundice beginning two weeks after starting ashwagandha, resolving within five months of withdrawal¹⁵. Products are sold as root, leaf, or combined extracts; see Form comparison¹³.

Hormone-sensitive prostate cancer is the most consequential exclusion, because ashwagandha may raise testosterone¹³. The NIH fact sheet lists possible interactions with diabetes, blood pressure, sedative, anticonvulsant, immunosuppressant, and thyroid hormone medications, and asks patients to discuss use with their health care providers¹³.

Last updated October 16, 2026. Read how we make monographs.

In the full monograph

85 sources, 67 studies

When to useThe situations practitioners use it for, each with the reason and the study behind it.
SafetyWho should avoid it, who needs extra care, and the side effects reported in studies.
InteractionsThe medicines and supplements it interacts with, the effect of each, and what labeling says to watch.
Protocol notesThe doses used in studies, how and when they were taken, and how the forms on the market compare.
How it worksWhat it is and how it works in the body, in plain terms.
Published studiesThe studies behind each use, popular claims checked against them, and trials still under way.
Word of mouthWhat patients and practitioners report online, kept separate from the clinical evidence.
Clinical perspectiveA closing read of where the evidence is solid, where it is thin, and what has not been studied.

Ashwagandha

Snapshot

In the full monograph

Articles

Sources