In the field of Pharmacotherapy the Unani system of medicine displays a unique wealth of knowledge and experience which went into the building up of this branch of treatment. According to Unani System of medicine drugs having states opposite to those present in the diseases should be applied. Natural drugs like plants, minerals and animal drugs are more advisable in this system. Some other principles related to Pharmacotherapy may be mentioned as under.
The Unani medicine presupposes that the drugs also have their own temperament due to their special constituents. Some drugs are composed of ingredients having opposite qualities, one quality acting in a way contrary to the other and these qualities are accommodated in two different parts of the drug. Ingredients possessing special actions are called active principles of the drugs. This theory of temperament of drugs is based on analogy and careful experiments.
Drugs are graded into four degrees according to their potency. In Unani system, drugs are used when the physical means and foods fail to cure a disease. Drugs of low potency should be used, as far as possible but according to the severity of disease, we may use high potency drugs. Drugs having greater potency are sometimes harmful. When a severe disease occurs and there is danger of complete loss of energies and life then drugs of higher potency can be used from the outset.
The mechanism or mode of action of a drug can be explained only partially. For example glycerrhizea causes expectoration by relaxing and opening the passage of broncheoles but why it does so cannot be explained. However the Unani physicians have tried to explain it as follows;
The direct action of a drug is the result of its physical or acquired characters. Drugs mainly act by (heat, coldness, moisture or dryness.)
Some of the drugs have peculiar characteristics which influence the body when these drugs are administered.
Actions of drugs n various systems or organs can be described in detail in the systematic pharmacology. Some drugs can act on peculiar organs only. For example the Anaesthetics act on the nerve-endings of sensory nerves.
Coctive is used to prepare the matters for excretion through purging or other means of excretion.
This mode of treatment is used particularly for treating chronic or obstinate diseases. Purgative is used generally followed by coctive.
While determining the dosage of a drug, factors such as temperament and potency of drugs, temperament and age of the patient, nature of disease, severity of the disease, route of drug, etc. must be kept in mind.
High potency drugs or severe purgatives and emetics should be avoided during summers and the severe cold weather. Different types of treatment are prescribed for different stages of the same disease. Some drugs should be used only when the stomach is empty such as anthelminthics while others should be used only after meals e.g. compounds of Iron. Mild action purgatives should be used at night and the sharp action purgatives in the morning.
In addition to oral drugs Unani physicians also administered drugs through Huqna, Abzan, Farzaja, Shiaf, Zimad and Tila etc. The inhalation through inspiration is also useful in curing many respiratory diseases.
Powders, Decoctions, Infusions, Distillates, Tablets, Jawarish, Majoon, Sharbat, Khameerajat, Bakhoor and Inkebab, Perfumes etc. are used to achieve the action of required active principles of drugs. Jawarish is used for stomach diseases and Lauooq for respiratory disorders etc.
The harmful effects are either corrected by simple methods or by compounding with other drugs, for example frying in oil decreases the irritant effect of the drug.
In Unani system of Medicine substitutes are generally selected in reference to one or more actions when a drug is not available or is too difficult to obtain but as far as possible it is avoided.
Rhazes (925. D.) has compiled a treatise titled Maqala fil-Abdal-il-adviyah-fit-tibb-wal-ilaj on the subject of medicinal substitutes wherein he has described the laws of selection of substitute of a drug and has mentioned substitutes of some 122 single drugs.