‘Jatharenagnina yogat yadudeti rasantaram |
Rasanam parinamante sa vipaka eti smrutaha ||’
-Ashtang hriday sutra.9

The final outcome of the biotransformation of the rasa of a given dravya through the action of jatharagni (digestive enzymes) i.e. end-product or the transformed state of ingested substance after digestion or metabolism is known as ‘Vipaka’.

Process of Vipaka / Pharmacokintics

After ingestion of bhukta dravya due to the action of agni, it alters in rupa and rasa; resulting in sara-kitta vibhajana.

Sara bhaga of bhukta dravya goes to hrudaya(heart) ; therefrom circulates in all over body with the help of vyan vayu. Then this sara bhaga resides in all dhatus and get metabolized by the respective dhatwagni. This aadyarasa and rasadhatu combinely causes vruddhi and kshaya of a perticular dhatu due to dhatuguna saamya and vishesha. Hence Vipaka is also assessed by dhatu vruddhi and kshaya.

Vipaka produces various pharmacological actions. Proper transformation gives beneficial effects resulting in samyaka vipaka or samyaka pratyayarabdha. While improper transformation gives side effects resulting in mithya-vipaka or vichitra pratyayarabdha.

Existance of Vipaka

The process of vipaka starts in grahani. The site of action of vipaka is described in text as: ‘Antahkoshte pakwashaye madhyamamarge mutrashaye tatha dhatushu cha drushyate |’. Charaka claims that Vipaka works at koshtagni level i.e. doshas level. It indicates his view of kriya-sharir. Sushrut said that guru and laghu Vipaka acts at dhatu level which is of clinical importance.

Mode of Action of Vipaka

According to Chakrapani, there are 2 types of dravyas viz. Aahara dravya and Aushadhi dravya. Aahara dravyas are mainly Rasapradhana. Here Rasa means Rasa dhatu and Dhatwagni is responsible for its functioning. On the other hand, Aushadh dravyas are Viryapradhana. As Virya is a gunatmaka entity, bhutagni helps in its functioning. Therefore Aaharadravyas mainly undergoes Dhatwagnivyapara and aushadhadrvyas undergoes bhutagnivyapara. From jatharagni paka to the bhutagnivyapara in the liver, there is functioning of rasa. After bhutagnipaka the process of vipaka starts and it ends with the bio-transformation of rasa.

Determination / Assessment of Vipaka

‘Vipakaha karmanishtaya|’

It can be assessed by its karma on dosha, koshta & dhatu.

1. Bhoutikagni helps in production of doshas
2. Jatharagni i.e. koshtagni generates mala-mutra
3. Dhatwagni proliferates dhatus upto shukra.

Therefore Vipaka is a final transformative state achieved through all these agnis.

Types of Vipaka

There are different views & theories based on no. of Vipaka-

1) Shadavidha Vipaka-vada- ( Concept of 6 Vipakas)

1. Niyat or Yatha rasa Vipaka-vada-

(Definite Vipaka concept)-

Each rasa will undergo its individual Vipaka and result in 6 Vipakas respectively. But according to Sushrut and Nagarjuna thereare several exceptions - Eg. Vrihi (rice) is madhura rasatmaka; but amla vipaki. Similarly, Amalaki is Amla rasatmaka; but madhura vipaki. As Rasa and Vipaka are expressed and also acts upon the body at different times; sushruta opposes this concept.

2. Aniyat Vipaka-vada- Vipaka expressed by dominant rasa only.

2) Panchavidha Vipaka-vada-

Sushruta explained the Vipakas on the basis of Panchabhutas. Panchabhotika dravyas undergoes their respective bhutagni paka. Parthiva and Aapya vipakas are guru, while taijasa, vayavya and nabhasa dravyas are laghu vipaka. Therefore these 5 will come under 2 vipaka viz. Guru and Laghu.

‘Sarvam dravyam panchabhoutikam asminnarthe|’

All dravyas are panchabhoutika. After food ingestion, due to metabolism, panchamahabhuta get converted into simplified form from complicated one; which is nothing but pakakriya, called as ‘Vipaka’.

3) Trividha vipaka-vada--

‘Tridha vipako dravyasya swadwamlokatukatmakaha|’
Ashtang hrudaya sutra.1

Acharyas like Charaka, Vagbhata and Parashar emphasizes on trividha vipaka-vada.

-Madhura and Lavana rasa shows Madhura Vipaka’
-Amla rasa shows Amla Vipaka,
-While katu, tikta and kashaya rasa shows katu vipaka.

According to Parashara, instead of katu vipaka, tikta and kashaya rasa shows madhura vipaka as they are pitta shamaka. If correlated with modern sciences, Amla vipaka is considered as ‘amino acid formation’; Madhura vipaka is correlated with glucose formation by carbohydrate and starch metabolism; whereas Katu vipaka is correlated with formation of fatty acids and glycerol by fat metabolism.

4) Dwividha vipaka-vada-

Sushruta mentioned dwividha vipaka as Madhura and Katu vipaka. As madhura vipaka consists of guru , snigdha, sheeta, pichchhila gunas; it is called as guru vipaka.While Katu vipaka, due to its vishada, tikshna, ruksha, laghu gunas called as ‘Laghu Vipaka’. The transformation of food and drug material will end with genesis of either guru guna or laghu guna. Sushruta doesn’t considered Amla vipaka; as amla is a vitiated state of Pitta dosha. According to him, As considered so, then Lavana vipaka should also be considered as it is a vitiated state of kapha dosha. It seems that Charaka mentioned Vipaka concept mainly aiming at Aahara(food) as it is upto the level of tridoshas and rasas. On the other hand, Sushruta’s vipaka emphasizes on drug metabolism after which dravya shows their properties (gunas) on the body.

Charcteristics of Vipaka

1) Madhura Vipaka

1. Snigdha, guru
2. Kapha dosha and shukra dhatu vardhaka
3. Vaatanulomaka
4. Srushta vinmutra

2) Amla Vipaka

1. Snigdha
2. Laghupittavardhana
3. Shukranashana
4. Srushtavinmutra

3) Katu Vipaka

1. Ruksha, laghu
2. Vatavardhaka
3. Shukranashana
4. Badhdhavinmutra

Factors Altering Vipaka / Causes of Change in Vipaka

1) Dravya pramana (doses)
2) Sanskara (process of pharmacological preparation)
3) Satmya (Habit formation)
4) Agni balabala ( digestive power)
5) Desha (place)
6) Kala (time)
7) Samyog (different combinations)
8) Paka

Difference between Avasthapaka and Nishtapaka

Difference between Vipaka and Virya

Superiority of Vipaka

Superiority of vipaka is explained by Bhadanta Nagarjuna as follows- 

Due the formation of glucose, amino acids, glycerol and fatty acids, Madhura vipaka is guru. Amla vipaka is ‘lghu than madhura’ and ‘guru than katu vipaka’, as lactic acid and pyruvic acid are formed in this phase. Due to the presence of end product of cellular respiration, katu vipaka is most laghu in nature.

Cooked food (boiled starch) and kalpanas like kashaya, leha having agnisanskara undergoes salivary phase of digestion. On the other hand, Swarasa, kalka, churna doesn’t have any starch reaction. Therefore they are guru in nature.

In pharmacology, the secondary metabolites of the plants i.e. active principles etc. will undergo certain chemical changes inside the body under the influence of liver and tissue micro-enzymes resulting in respective pharmacological action. Therefore the drug effect produced through the process of metabolism shall only be considered as ‘Vipaka’. In this way, Vipaka can be correlate with Pharmacokinetics or drug metabolism dealt in modern pharmacology.

The article is written with the guidance of  Prof. Vd. B. S. Sawant Dravyagunavidnayan dept., Smt K.G.Mittal Punarvasu Ayu. College, Mumbai