Some historians of Ayurveda date Atreya to 6th century BCE, and theorize that he was the personal physician of the Gandhara king Nagnajita.
The Buddhist text Mulasarvastivada-Vinayavastu describes him as the teacher of Jivaka, the personal physician of the Buddha, and connects him to Takshashila in Gandhara.
According to Surendranath Dasgupta, The old Ayurveda of Atreya-Charaka school probably has its root in the now extinct Caranavaidya branch of Atharvaveda.
[3] According to the Charaka tradition, there existed six schools of medicine, founded by the disciples of the sage Punarvasu Ātreya.
According to Dr. Tustomu Yamashita, the Bhela or Bheda(la)Samhita is often quoted by later authors and commentators of Ayurveda.