The knowledge we have now is by three surviving texts of Charaka, Sushruta and Vaghbata. Charaka (1st century A.D.) wrote Charaka Samhita (samhita- meaning collection of verses written in Sanskrit).  ushruta (4th century A.D.) wrote his Samhita i.e Sushruta Samhita.

Vaghbata (5th century A.D.) compiled the third set of major texts called Ashtanga Hridaya and Ashtanga Sangraha. Charaka’s School of Physicians and Sushruta’s School of Surgeons became the basis of Ayurveda and helped organize and systematically classify into branches of medicine and surgery.

Sixteen major supplements (Nighantus) were written in the ensuing years – Dhanvantari Bahavaprakasha, Raja and Shaligrama to name a few – that helped refine the practice of Ayurveda. New drugs were added and ineffective ones were discarded. Expansion of application, identification of new illnesses and finding substitute treatments seemed to have been an evolving process. Close to 2000 plants that were used in healing diseases and abating symptoms were identified in these supplements.

Dridhabala in the 4th century revised the Charaka Samhita. The texts of Sushruta Samhita were revised and supplemented by Nagarjuna in the 6th century.

Sixteen major supplements (Nighantus) were written in the ensuing years – Dhanvantari Bahavaprakasha, Raja and Shaligrama to name a few – that helped refine the practice of Ayurveda. New drugs were added and ineffective ones were discarded. Expansion of application, identification of new illnesses and finding substitute treatments seemed to have been an evolving process. Close to 2000 plants that were used in healing diseases and abating symptoms were identified in these supplements.

Dridhabala in the 4th century revised the Charaka Samhita. The texts of Sushruta Samhita were revised and supplemented by Nagarjuna in the 6th century.

The system, Ayurveda, has been in continuous practice for more than 2000 years.  The treatments done with the help of Natural Healing Power of Herbs were in use since 5000 years.  Our ancestors developed this method and results obtained were recorded.  As in the case of other branches of Science, Research and Investigations were systematically done, method of treatments to get maximum output were developed and crodified to make it un-challengeable.

History of native Indian Medical Science is probably as old as the Indus Valley Civilization dating back to 3000 BC. The remains of deer antler and bitumen found in Harappa bear evidence to the existence of a Medical Science. It was between 1200 and 700 BC subsequent to the Aryan Invasion. So that the four sacred Vedas were composed. References to diseases, Herbs and herbal cures can be seen in all the four Vedas especially in Rig Veda.