Dhanvantari is depicted as Vishnu with four hands, holding Shankh , Sudarshan Chakra, Jalouka (Leech ) and a pot containing rejuvenating nectar called amrita in another. He is often shown with a leech in his hand rather than the scriptures. Bhagavapurana states that Dhanavantari emerged from the Ocean of Milk and appeared with the pot of nectar during the story of the Samudra or Sagar manthan whilst the ocean was being churned by the devas and asuras, using the Mandaramountain and the serpent Vasuki. The pot of Amrita was snatched by the Asuras or Demons, and after this event another avatar, Mohini, appears and takes the nectar back from the Asuras. It is also believed that Dhanvantari promulgated the medical science of Ayurveda.
According to ancient Sanskrit work Vishnudharamottara , lord Dhanvantari is a handsome individual and should usually depicted with four hands, with one of them carrying Amrita, the ambrosia of god. Since he is considered Vishnu himself, two of his hands are depicted carrying regular Vishnu symbols the Chakra and the Sankha.
Dhanteras is celebrated by the practitioners of Ayurveda every year, two days before Deepavali, the Hindu festival of Lights.
Om namo bhagavate vasudevaya