Ashwagandha (Withania somnifera) has long been used in Ayurvedic medicine to promote overall well-being, support stress reduction, and improve sleep quality. Its traditional use as a "rasayana" or rejuvenator is well documented, and it is often recommended for people experiencing insomnia or disturbed sleep due to stress or anxiety. However, the specific use of ashwagandha to treat or prevent nightmares is not prominently featured in classical Ayurvedic texts or ethnobotanical literature. Most references to ashwagandha's sleep-supporting properties focus on its adaptogenic effects—helping the body cope with stress and potentially leading to improved sleep patterns.

Scientifically, research has largely concentrated on ashwagandha's anxiolytic (anti-anxiety) and mild sedative effects, which could theoretically contribute to fewer nightmares if those nightmares are related to stress or anxiety. Still, there are no robust clinical trials directly investigating ashwagandha as a treatment for nightmares. The very limited evidence that does exist is largely anecdotal or speculative, based on its role in calming the mind and supporting restful sleep. Therefore, while ashwagandha may be traditionally used to promote better sleep and reduce stress, its specific use for nightmares is not strongly supported by either historical documentation or scientific research.