The Guna (quality) of a substance or drug is represented by its Rasa. The Dravyas are classified into six categories according to the six Rasas.

1. Madhura Rasa (sweet)
Sweet taste promotes handsomeness and longevity and tones up the Ojas (vitality). It helps restore the vitiated humor Pitta and alleviates morbid Vata humour.

2. Amla Rasa (acidic)
It stimulates the salivary glands and promotes appetite and digestion. It provokes the humors Kapha and Pitta.

3. Lavana Rasa (saline)
It enhances the flavour of food. It acts as a carminative and a laxative and allays Vata humor.

4. Katu Rasa (pungent or acrid)
It acts as an anthelmintic, dilates the body channels and allays the Kapha humor.

5. Tikta Rasa (bitter)
It is parasiticidal and antipyretic. It is also a carminative.

6. Kashaya Rasa (astringent)
Soothes the Kapha and Pitta humors when they are irritated.