Once, Lord Indra the leader of the Devas, drew the ire of Sage Durvasa, as a result all Devas were cursed to lose their energy & vitality. Seeing this, Asuras - the arch enemies of the Devas, quickly began attacking their domain & inflicting pain and torture.
Bhagavata Purana speaks about another Dhanvantari – a human - who the son of Dhirgatama in the Pururava dynasty. It was this Dhanvatari who created a 5th Veda – Ayurveda & divided it into 8 divisions for practice.
Divodasa Dhanvantari is believed to have lived around 3000 BC & was the teacher of Susruta, the famous Ayurvedic physician and is prominently mentioned in the Susruta-Samhita. He was responsible for the definition of Ayurvedic surgery recorded by Susruta.