The word deepana literally means kindling, inflaming, setting on fire etc. It also represents digestive or stimulating action. In Ayurveda deepana represents kindling the digestive fire. As far as the Ayurvedic treatment is concerned deepana is considered as an independent treatment method as it is one among the pacification therapies [A.Hr.Sutra Sthana.14/6]  and as a prerequisite for purificatory procedures. [A.Hr Sutra Sthana 13/29]
Etymology and derivation
The word deepana is derived from the word ‘deepa’ which means ‘kindling the fire’ with ‘nich’ and ‘lyu’ suffix. [Vachaspatyam]
The process of increasing the digestive fire without the digestion of toxic waste products (ama) is called deepana.
Deepana, sandeepana, agni deepana
Importance of deepana
Digestive fire (Agni) is one of the most important concepts in Ayurveda. A qualitative or quantitative reduction in the digestive fire is considered as the cause for all diseases.[A.Hr.Nidana Sthana.12/1] Maintaining the digestive fire in its normal level is essential to maintain health. Deepana helps to kindle the digestive fire.
The deepana property is attributed to a wide range of drugs, food materials and even some of the regimens also. Among them the best material which increases the digestive fire is fats/oils (sneha) [Cha.Sa.Chikitsa Sthana 15/201]. The drugs which possess the deepana property is having the predominance of Agni mahabhuta.[Su.Sa.Sutra Sthana.41/6]
- The tastes (rasa) which have deepana property : Salt (lavana), Bitter (tikta) [Cha.Sa.Sutra Sthana 26/43], Spicy (katu) [Su.Sa.Sutra Sthana.42/10]
- Drugs which possess deepana property: Anethum sowa(shatapushpa), Tinospora cordifolia (guduchi), Azadirachta indica(nimbi), Sentalum album(chandana), Prunus cerasoides(padmaka), Piper longum(pippali), Piper nigrum(maricha), Zingiber officinale(sunti),Aegle marmelos(bilwa), Clerodendrum phlomidis(agnimanda), Cyperus rotundus(musta), Terminalia chebula(haritaki) etc.
- Food items which possess deepana property: Hot water [Su.Sa.Sutra Sthana.45/39], coconut water [Su.Sa.Sutra Sthana.45/43], cow’s milk , breast milk[Su.Sa.Sutra Sthana.45/57], buttermilk, alcohol, honey, salt, asafoetida etc.
- Regimen which possess deepana property: Bath [A.Hr.Sutra Sthana.2/16] 
Importance in preservation of health and prevention
In rainy season the digestive fire is naturally less because of the effect of season and there is aggravation of all the doshas. So the person should follow the diet and drugs which have deepana property in order to prevent the occurrence of diseases. [Su.Sa.Uttaratantra.64/7]
Importance in management of disease
Deepana is indicated in large number of diseases. Few examples are the following
- in the treatment of fever (jwara) with hotwater [Cha.Sa.Chikitsa Sthana 3/144]
- in kapha gulma with buttermilk (takra) [Cha.Sa.Chikitsa Sthana 8/119]
- in grahani roga with buttermilk [Cha.Sa.Chikitsa Sthana 15/117]. Deepana is always indicated in all types of grahani disease.[Su.Sa.Uttaratantra.40/182]
- for patients of tuberculosis (rajayakshma) suffering from bouts of diarrhea (atisara). [Cha.Sa.Chikitsa Sthana 8/134]
- for the removal of distaste in the mouth.[Cha.Sa.Chikitsa Sthana 8/136]
- for the treatment of debility due to injury(kshatakheena).[Cha.Sa.Chikitsa Sthana 11/84]
- for the treatment of piles/hemorrhoids (arsha). [Cha.Sa.Chikitsa Sthana 14/250]
- for the treatment of morbid undigested material ama which gets stuck inside the intestine (pakvasaya) [Cha.Sa.Chikitsa Sthana 15/75]
- in the beginning stages of cough caused due to emaciation (kshayaja kasa) [Cha.Sa.Chikitsa Sthana 18/150]
- vata lodged in the alimentary tract.[Cha.Sa.Chikitsa Sthana 28/89]
- If vata is occluded by food (annavruta vata) [Cha.Sa.Chikitsa Sthana 28/196]
- Occlusion of apana vata by samana vata [Cha.Sa.Chikitsa Sthana 28/206]
- Occlusion of udana vata by apana vata[Cha.Sa.Chikitsa Sthana 28/211]
- For the treatment of distension of abdomen(admana) [Su.Sa.Chikitsa Sthana.5/26]
The medicines should be administered along with the food in order to attain the deepana effect. [Su.Sa.Uttaratantra.64/75]
As a prerequisite for purification therapy
Before purificatory therapies digestive(pachana), deepana, oleation and sudation therapies should be performed. Through deepana the doshas gets detached from the body tissues or body channels [Hemadri on A.Hr Sutra Sthana 13/29] and thus facilitates an easy, effective and safe purification therapy.
After the purification therapy
After the purification procedures, the power of the digestive fire diminishes. To bring back the digestive fire to its normalcy the diet plan which has deepana property should be advised. In case of bloodletting also after the procedure, the need to protect the digestive fire is highlighted. [A.Hr.Sutra Sthana.27/52]
Some of the medicines with deepana property
- Taleesadi churna [Cha.Sa.Chikitsa Sthana 8/146]
- Takrarishta [Cha.Sa.Chikitsa Sthana 14/75]
- Pippalyadi gritha [Cha.Sa.Chikitsa Sthana 14/118]
- Dantyarishta [Cha.Sa.Chikitsa Sthana 14/147]
- Dadimadi gritha [Cha.Sa.Chikitsa Sthana 16/46]
- Kantakari gritha [Cha.Sa.Chikitsa Sthana 18/35]
- Ashtangalavana [Cha.Sa.Chikitsa Sthana 24/178] etc.
Ghrelin is an orexigenic hormone secreted from the stomach. The concentration of ghrelin in plasma has been reported to rise before food intake and it falls after the ingestion of food. While administered peripherally there was an increase in food intake and it also activates a group of neurons in hypothalamus called AgRP(agoutirelated peptide) neurons. Asprosin is another orexigenic hormone that activates AgRP directly.
In animal studies, it is observed that AgRP neurons become activated when there is deficiency in calories and becomes less active when they are fed. In already fed animals when the AgRP neurons were activated through chemical or light stimulus they start to eat intensely. So these neurons are considered as hunger promoting neurons.
Leptin is an anorexigenic hormone secreted by adipose tissue. Its main function is to maintain adequate fat storage in body. A fall in leptin level stimulates hunger.
The mode of action of deepana drugs is still unclear. More research works are needed in this regard to show whether deepana is having any action over hormones, neurons etc.
List of theses done
- Jaidev Gehija (2018): Efficacy of Paushtika biscuit with and without deepana pacahana in the management of karshya (Malnutrition) – An open-labeled, randomized, comparative clinical trial. Department of Kaumara Bhritya, IPGT&RA Jamnagar
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