As there is not a single disease, which can make its appearance without the participation of any of the deranged bodily humours, a wise physician is enjoined to administer medicines according to the specific features of the deranged humours involved in a disease whose nature and treatment have not even been described in any book on medicine. The different seasons of the year have been described before.
In the cold season, a disease should be treated with measures and remedies endued with the virtue of destroying or warding off cold, while in summer the medicinal treatment should consist of measures and applications capable of allaying the heat. The medical treatment of a disease should be commenced just at the opportune moment, which should not be allowed to expire in vain under anycircumstances whatsoever. A course of medical treatment commenced at an inopportune moment, or not resorted to at the advent of its proper time, as well as over or insufficient medication, proves abortive even in a curable type of disease. The proper medical treatment (of a disease) is that which successfully copes with the malady under treatment, and arrests the recrudescence of a fresh one by way of sequel, and not that, which, though subduing a particular distemper, is immediately followed by a new one.
It has been demonstrated before that the food of a man is digested only with the help of the digestive fire or heat (Pachakagni), which may be divided into four different kinds (states). One of these kinds is due to it not being in any way affected by the deranged humours of the body, while the other three are respectively ascribed to the fact of their becoming so deranged. The digestive fire or heat becomes irregular or fitful (Vishamagni) through the action of the deranged Vayu, becomes keen, through the action of the deranged Pittam, and dull or sluggish, through the action of the deranged Kapham. The fourth kind (Sama) continues in a state unaffected by any of the morbid humoural constituents of the body owing to their maintaining the normal equilibrium.
Samagni and Vishamagni - The digestive heat, which fully digests the ingested food at the proper time without the least irregularity, thus reflecting the continuance of the bodily humours in their normal state, is called Samagni. The digestive heat which is irregular in its action, and which sometimes helps the process of complete digestion, and produces distension of the abdomen, colic pain, constipation of the bowels, dysentery, ascites, heaviness of the limbs, rumbling in the intestines, and loose motions (diarrhoea) at other times, is called Vishamagni.
The digestive heat, which helps the digestion of even a heavy meal within an incredibly short space of time, is called "Keen" (Tikshnagni) and which becoming abnormally augmented begets an excessive or voracious appetite (Atyagni), helps a glutton to digest his frequent meals, and produces a parched throat, palate and lips, heat and other discomforts.