For understanding the present action of Deepana, it is very important to know the concept of AGNI. This is due to the fact that AGNI is being mainly affected by the introduction of the substances that exhibit this action. As the definition goes AGNI becomes UDEEPANA (Energize or activate) with the intake of these class of substances. The concept of Agni refers to three types namely AGNI at the level of Amashaya (Jataragni), Dhatu (Dhatvagni) and Mala (Malagni). Thus the substances that exhibit this property will have the capacity to energize or activate any of the three or all the three in general. But under general understanding, the Agni being referred to as Jataragni, this is being the basic parameter to assess the action of the substance. The main physical parameter to assess this action is increase in Appetite. But when the substance has the effect on the increase of Agni at the Dhatu (Tissue) level, then the evidence is understood to have increase in the need of energy for the functioning of the body tissues. As the definition clearly tells that the substance with Deepana action will not have the ability to Digest ‘AMA’, this implies that it can only increase the ability of the body or tissue or cell to increase the ability to ingest or accept nutrition but not result in transformation or metabolism. Sharangadhara Samhita mentions another activity namely “PACHANA” which describes the activity namely “increase of metabolism”. But Charaka has included both the categories in the same group of DEEPANEEYA itself. 

It is very evident that as the action is more concerned with AGNI, the substances should have those properties that have the involvement of AGNI Mahabhuta namely ‘KATU, AMLA & LAVANA RASA; LAGHU, RUKSHA OR SNIGDHA (property seen in Pitta Dosha alone even though being derivative of AGNI), TEEKSHNA & SUKSHMA GUNA; USHNA VEERYA and KATU or AMLA VIPAKA. 

Other than AGNI, there is also involvement of SAMANA VAYU in the increase of appetite along with KLEDAKA KAPHA. But among the two SAMANA VAYU has more prominence as it instigates AGNI thus giving a DEEPANA effect. Hence a substance with KATU RASA, KATU VIPAKA, LAGHU, RUKSHA GUNA and USHNA VEERYA will be more efficient than without these properties.