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PRINCIPLES OF DRUG ACTION

The Ayurvedic Science delineated important three principles (Trisutra) viz., etiology (Hetujnana), symptomatology (Lingjnana) and therapeutics (Oushadhajnana). Etiology includes the immediate and distant cause of diseases. Similarly the symptomatology includes the entire signs and symptoms of diseases and health and the therapeutics include wholesome diet along with the treatment of diseases. Ayurvedic concepts of pharmacology are included under Oushadhajnana.

Correct Application of the drug is essential:

The goatherds, shepherds, cowherds and other forest dwellers know the drugs by name and form. No one can know the principles governing correct application of drugs simply by knowing their names and forms. A physician, even ignorant of their forms can be said to be a knower of the essence [of science] if he is acquainted with the principles governing the correct application of drugs, let alone the one who knows drugs in their entirety. One who knows the principals governing their correct application in consonance with the place, time and individual variation, should be regarded as the best physician. Of course, the best physician is he who is well acquainted with the drugs in their entirety.

One has to establish the correct identification of drug prior to its collection. Sushruta suggests that the knowledge of identification of herbs can be obtained by contact with cow-herds, herds, hermits, hunters and others who roam in jungles and take root (of plants) as food.

A drug not known is likened to poison, weapon, fire and thunderbolt

Basic concepts of Ayurvedic pharmacology 28 while the one known, to the nectar. A drug known in respect of its name, form and properties or even if known, improperly administered, leads to bad consequences.

Proper application of drugs depends upon their proper knowledge.

Unless the physician knows the drugs properly he cannot cure a patient; his prescription would rather kill his patient. The drug unknown, might act as poison which kills after bringing about unconsciousness or as a weapon which kills after piercing through the vital organs, or like fire which kills by causing boils, etc. or as a thunderbolt which kills instantaneously. It is only when a physician knows all the three aspects, viz., name, form and properties of drugs. The physician can treat the patients successfully.

Even an acute poison can become an excellent drug if it is properly administered. On the other hand even a drug, if not properly administered, becomes an acute poison. So a wise patient desirous of longevity and health should not accept any medicine prescribed by a physician ignorant of the principles governing its application. Some times, one might escape (death) even when thunderbolt of Indra has fallen on his head, but one can never survive if he takes medicine prescribed by a physician ignorant of the application.

To sum up, neither the patient should take medicine prescribed by pseudo-physicians, nor a physician, without being proficient in the principles governing the application of drugs.

Only that, which can bring about a cure, is a correct medicine. It is only he who can relieve his patients of their ailments is the best physician.

Basic concepts of Ayurvedic pharmacology 29 For the purpose of the Science of medicine, it is necessary to explain the qualities of correct medicine and a good physician. It is only that which possesses the requisite curative values is to be treated as a correct medicine.

As regards physician, he should first of all know the principles underlying the correct application of medicines. Unless he knows it, he will not be able to relieve his patients of their ailments. Even if per chance, medicines selected by him at random succeed in alleviating ailments, the credit is considered as accidental one.

Classification of Dravya:

Akasa etc., (Prithvi, Ap, Tejas, Vayu and Akasa), soul, mind, time and space constitute matter. Matter having sense organs is sentient while the one devoid of them is insentient.

Chakrapani Dutta interprets that “This definition applies also to the vegetable kingdom; that is to say the vegetable kingdom is also sentient.

Many examples can be cited to prove this. The Suryabhakta (Helianthms annus Linn.) moves according to the movement of the sun. The Lavali (Gicea acida Merrill) gets fruits just on hearing the sound of the thunder.

The Bijapuraka (Citrus medica Linn.) tree produces fruits only by the smell of the fat of jackals etc., similarly Amra (Mangifera indica Linn.) trees when irrigated with the fat of fish, produces fruits in plenty. Ashoka tree (Saraca indica Linn.) hit with the sole of the feet of a lady begets flowers. The above example clearly indicates the presence of the various sense organs in the vegetable kingdom as well. This is also attested from scriptures. “If a Brahmin does not give blessings in response to salutations, he is born in a cemetery as a tree surrounded by vultures and Kankas.” “Trees, shrubs and other varieties of grass are covered with darkness arising out of their sinful

Basic concepts of Ayurvedic pharmacology 30 acts but they all have consciousness full of happiness and miseries. The extent of creation beginning with Brahma is up to vegetable kingdom.”

Thus, the members of the vegetable kingdom have got life as well as consciousness. So they belong to category of sentient matter”. Vedic lorwe clearly indicated that plants do have life and modern scientists like Jagadish Chandra Bose have tried to revalidate these concepts through scientific experiments.

Drugs are of three categories, some alleviate Doshas, some vitiate Dhatus and some are good for the maintenance of positive health.

This three-fold classification of drugs also includes other type of drugs which are responsible for elimination and suppression of Doshas.

Elixirs and aphrodisiac drugs come under the third category which are responsible for the maintenance of positive health.

The use of the term “Dosha” and “Dhatu” in the first and second category of classification is quite significant. “Doshas” include “Dhatus”

and Vice-Versa. So the drugs that are designated as alleviators of the Doshas also alleviate Dhatus. Similarly, the drugs that have been designated as vitiators of the Dhatus do as well vitiate Doshas. The drugs under the third category are those which have potentialities to maintain the positive health.

Apparently it also means that the drugs have got potentialities to prevent the diseases.

According to another classification, Dravyas are of three kinds viz., those of animal origin, those of vegetable origin and metals including minerals. Different types of honey, products of cow milk, bile, fats of

Basic concepts of Ayurvedic pharmacology 31 muscle tissue, marrow, blood, flesh, faeces, urine, skin, semen, bone, ligament, horn, nail, hoof, hair, Lomana, (hair of the body excluding those of the head and face), Rochana (purified Ox bile) - are some of the drugs of animal origin used in medicine.

Gold, five Lohas (copper, silver, tin, lead, and iron) along with their byeproducts (different types of bitumen), calcites along with silica, red arsenic, yellow arsenic, gems, salt, red chalk, collyrium – are in brief the metals and minerals used in medicine.

The drugs of vegetable origin are of four types viz. Vanaspati, Vaanaspatya, Virudh, and Oshadhi. Vanaspati is the one having fruits only (without flower). Vaanaspati has flowers as well as fruits. The drugs belonging to the class of Virudh are those which spread with branches.

Oshadhis are those which die out when their fruits mature. The root, bark, Sara (aqueous extract), secretions, fibre, juice, tender leaves, alkali preparations, latex, fruits, flowers, ashes, oils, thorns, matured leaves, adventitious roots, rhizomes, sprouts are belonging to the group of drugs of vegetable origin.

In another classification the drugs are classified according to part used viz., Moolini (Root) and Phalini (fruits). The Mula (Root), Twak (bark), Sara (heartwood), Niryasa (Secretions/gums), Nala (fibre), Swarasa (juice), Pallava (tender leaf), Kshara (Alkali), Ksheera (latex), Phala (fruit), Bhasma (Ash), Taila (oil), Kantaka (Thorn), Patra (leaf), Sunga (adventitious roots), Kanda (rhizome), Praroha (sprouts) are the useful parts of the drugs of vegetable origin. Charaka also describes the plant with useful parts like roots

Basic concepts of Ayurvedic pharmacology 32 and fruits which are indicated in Panchakarma measures. He further explains about the drugs that are useful for various elimination (sodhana) therapies in Apamarga Tanduliyaka (Dehusked seeds of Apamarga) chapter. Drugs are of two kinds – one variety of drugs is used for internal cleaning (Abhyantara Parimarjana) and the other for external cleaning (Bahi Parimarjana). The drugs related to later category are described under Aragwadhiyam chapter.

In the chapter entitled ‘Satvirechana Satashritiyam’ the drugs useful both for internal as well as external cleansing are being explained. In this chapter fifty groups consisting of ten drugs each on the basis of pharmacological actions as well as therapeutic utility are introduced by Charaka which are popularly known as Dasaemani. In total five hundred drugs are listed among fifty groups and the same drug is repeatedly quoted in a number of groups of decoctives. After elaborative descriptions about the drugs of different groups Charaka humbly states that “the description of 500 decoctives (Mahakashaya) is neither too exhaustive nor too brief. Physicians of lower intelligence will, of course, find this list useful enough in the treatment of various diseases but those possessing high intellectual caliber need not confine themselves to this list. Physician may exercise his own imaginative power in finding out other similar drugs as well, according to the principles laid down in Ayurveda and keeping in view the requirements of the patient.

Dravya Pradhanya – (Importance of the substance):

Dravya (substance) is the chief (most important) among Rasa (tastes) and others qualities; because all of them (qualities) are residing in it (substance).

Basic concepts of Ayurvedic pharmacology 33 It (substance) is Panchabhutatmaka (composed of, born from the five elements), it has Ksma (Prithvi Bhuta) as its substratum (mass, support), it takes origin from Ambu (Apbhuta), Agni (Tejas Bhuta), Pavana (Vayu Bhuta) and Nabhas (Akasa Bhuta), with their intimate (inseparable) combination making for its formation and specify (of each substance). Its identification/designation is by preponderance (predominance, of the Bhuta present in it).

Nothing is Non – Medicinal

There is nothing in this universe, which is non-medicinal, which cannot be made use of for many purposes and by many modes.

Origin of substance takes place by combination of Prithvi, Ap, Tejas, Vayu and Akasa. Only predominance of one of them creates distinctions such as this is Parthiva, this is Apya, this is Taijasa, this is Vayavya and this is Akasiya.

Parthiva Dravya Lakshana (Qualities of Parthiva substances)

The substance which possesses qualities such as Guru (heaviness), Sthula (bulky), Sthira (stable) and predominant in Gandha (smell) is Parthiva (earthy); it bestows heaviness, stability, compactness and growth.

Apya Dravya Lakshana (Qualities of Apya substances)

The substance which possesses qualities such as Drava (liquidity), Sita (cold), Guru (heaviness), Snigdha (unctuousness, moisture, oiliness), Manda (dull), Sandra (thickness, dense) and predominant in Rasa (taste) is Apya (watery); it confers lubrication (moistness), secretion (moisture, production), Kleda (keeping wet), satiation (contentment, satisfaction) and cohesion (binding, holding together).

Basic concepts of Ayurvedic pharmacology 34 Agneya Dravya Lakshana (Qualities of Agneya substances)

The substance which possesses qualities such as Ruksha (dry), Tikshna (penetrating, sharp), Ushna (hot), Vishada (non-slimy), Sukshma (minute) and predominant in Rupa (appearance, showing, from); it causes burning sensation, lustre, expression of colour and digestion (process of transformation, putrefaction etc.)

Vayaviya Dravya Lakshana – (Qualities of Vayaviya Substances)

Vayaviya substance possesses qualities such as Ruksha (dry), Vishada (non-slimy), Laghu (lightness) and predominant in Sparsa (touch tactile sensation), it produces dryness, lightness, transparency, movements (different kinds of activities) and exhaustion.

Nabhasa Dravya Lakshana – (Qualities of Nabhasa Substance)

Nabhasa (Akasiya) substance possess qualities such as Sukshma (minuteness), Visada (transparence, clearness), Laghu (lightness) and predominant in Sabda (sound, hearing); it produces cavitation (hollowness) and lightness (weightlessness).

Purgative drugs are predominant in qualities of Prithvi and Ap which are heavy and as such move downwards, hence, by inference, purgative is predominant in qualities of down-moving elements eg. Prithvi and Ap;

emetic drugs are predominant in qualities of Agni and Vayu which are light and as such move upwards, hence emetic is predominant in qualities of up-moving elements e.g. Agni and Vayu. That acting in both ways in predominant in qualities of both the above two; pacifying drug is predominant in qualities of Akasa; astringent drug is predominant in qualities

Basic concepts of Ayurvedic pharmacology 35 of Vayu because of its drying nature; Dipana (stimulating digestive fire) is predominant in qualities of Agni because of its similarity; Lekhana (decreasing body-weight) is predominant in qualities of Vayu and Agni;

Brimhana (increasing body-weight) is predominant in qualities of Prithvi and Ap. In this way, action of drugs may be interpreted by inference.

Here heaviness and lightness should be taken as governed by specific potency situated in Trivrit, Madana etc. and not in the ordinary sense otherwise fish, floury food, lentils etc. would be purgatives and grey partridge, quail etc. might come into the emetic group; Lekhana – decreasing body-weight, by depleting Kapha and fat.

Vayu is pacified by substances composed of Prithvi, Tejas and Ap;

Pitta is pacified by those composed of Prithvi, Ap and Vayu while Kapha is pacified by substances composed of Akasa, Tejas and Vayu. (On the contrary), Vayu is increased by substances composed of Akasa and Vayu, substance which is igneous in nature increases Pitta while Kapha is increased by those composed of Prithvi and Ap.

In this way, in every substance, the predominance of qualities should be observed and, considering its effect on two or more Doshas, that should be applied in case of aggravated Doshas.

Drug classification according to Rasa (According to Sushruta):

Substances in reference to all are enumerated such as Kakolyadi group, milk, ghee, muscle-fat, marrow, Sali and Sastika rice, barley, wheat, blackgram, Sringataka, Kaseruka, Trapusa, Ervaruka, Karkaruka, Alabu, Kalinda, Kataka, Gilodya, Priyala, Pushkarabija, Kashmarya, Madhuka,

Basic concepts of Ayurvedic pharmacology 36 Draksha, Kharjura, Rajadana, Tala, Narikela, products of Ikshu (sugarcane), Bala, Atibala, Kapikacchu, Vidari, Payaysa, Gokshura, Kshiramorata, Madhulika, Kushmanda etc. are included in the sweet group.

Dadima, Amalaka, Matulunga, Amrataka, Kapittha, Karamarda, Badara, Kola, Prachinamalaka, Tintidika, Koamra, Bhavya, Paravata, Vetraphala, Lakucha, Amlavetasa, Dantasatha, curd, buttermilk, Sura (alcoholic beverage made of barley), vinegar, different types of sour gruel etc. are included in the sour group.

Saindhava, Sauvarchala, Vida, Pakya, Romaka, Samudraka, Paktrima, Yavakshara, that obtained from desert, Suvarchika etc. are briefly, the members of the salty group.

Pippalyadi, Surasadi, Sigru, Madhusigru, Mulaka, Lasuna, Sumukha, Sitasiva, Kustha, Devadaru, Harenuka, Bakuchiphala, Chanda, Guggulu, Musta, Langali, Sukanasa, Pilu etc. and mostly Salasaradi group come in the pungent group.

Aragvadhadi, Guduchyadi, Mandukaparni, sprouts of Vetra, two types of Haridra, Indrayava, Varuna, Vikankata, Saptaparna, two types of Brihati, Sankhini, Dravanti, Trivrit, Kritavedhana, Karkotaka, Karavellaka, Vartaka, Karira, Karavira, Jati, Sankhapushpi, Apamarga, Trayamana, Katuka, Vaijayanti (Tarkari), Suvarchala, Punarnava, Vrischikali, Jyotismati etc. briefly, come in the bitter group.

Nyagrodhadi, Ambasthadi, Priyangvadi, Rodhradi, Triphala; fruits of Sallaki, Jambu, Amra, Bakula, Tinduka, Saka and Nyagrodha etc;

Basic concepts of Ayurvedic pharmacology 37 Pasanabheda, mostly Salasaradi group, Kuruvaka, Kovidara, Jivanti, Chilli, Palankya, Sunisannaka etc. and Varaka, Mudga etc. are included in the astringent group.