With origins on the Indian subcontinent (India, Pakistan, Sri Lanka, and Bangladesh) Ashwagandha has a variety of herbal uses. Used primarily as an immune booster, Ashwagandha is considered to be a rasayana herb, a term that means ?rejuvenation? in ayurvedic medine. Roughly translating into ?knowledge of long life,? Ayurvedic medicine dates back to ancient India.