Guna - Rasa - Virya - Vipaka - Prabhava Siddhanta

Guna -  Rasa - Virya - Vipaka - Prabhava Siddhanta :

These five important, active principles of drug substances are follows :

I) Rasa : Therapeutically active agent.

II) Guna : Best quality

III) Virya : An active principle

IV)  Vipaka : The end product of digestion.

V) Prabhava : Actual therapeutically activity of the drug in the individual  on the drug in the individual.

These five principles are the Panchsheel or five pillars of the Ayurvedic therapeutic.