Introduction
Ayurveda is the science which literally means ‘the science of life’. It is also known as Indian system of medicine. Ayurveda is an ancient medical system, which treats what is advantageous and what is harmful for the body and stresses on happy and unhappy states of life. In other words, Ayurvedic system of medicine gives importance to the involvement of the patient’s well being.
Method of Preparation, Dose and Comparison
Ayurvedic Pharmacy
Ayurvedic Pharmacy is a Vast subject. Drug formulation in Ayurveda is based on following Seven Parameters:
- Dravya (Substance)
- Rasa (Taste)
- Guna (Property)
- Virya (Potency)
- Vipaka (Post-digestion effect)
- Prabhva (Specific action)
- Karma (Pharmacological activity)
Ravya is described as a substance used for medicinal purpose. According to Ayurvedic theory, every component of the universe is dravya and has medicinal value. Charaka Samhita has described dravya to be the nucleus of Ayurvedic pharmacy.
Taste has a significant place in Ayurvedic medicine. Diagnosis of a disease is based on three biological humours (vata, pitta, and kapha) and treatment is based on six tastes (sweet, sour, salt, pungent, bitter and astringent). Our tongue experiences these tastes when the drug is administered orally.
Guna is a vast topic. Ayurveda has described forty-one properties, which are comparable to physical properties of the drugs. Each property description has a specific role to play in the Ayurvedic drug formulation.
Virya (potency) is described as the active constituent of the drug and is responsible for the pharmacological activity of the drug. The drugs have cold and hot potencies.
Vipaka and prabhava parameters are comparable with metabolism and specific action of the drug.
Karma parameter describes the pharmacological activity of a drug in detail.
Ayurvedic Pharmacopoeial Preparations
Ayurvedic pharmacopoeial preparations are known as Panchakashaya kalpana. It is topic of Bhaishajya Kalpana, a full-fledged subject of Ayurvedic curriculum.
Panchakashaya Kalpana Includes:
- Swarasa
- Kwatha
- Phanta
- Shita
- Churna
Chief Ayurvedic Pharmacopoeial Preparations are Discussed Below:
Decoction
Decoction is the process of boiling in water coarsely comminuted vegetable drugs for a definite period.
Before preparing decoction the drug should be sliced before it is boiled in water for five minutes or longer. If the comminution is too fine some sediment deposits.
After preparing decoction it should be stored in sterile bottles. Before pouring into bottles, the decoction should be strained instead of filtering.
The decoction should be discarded if change in color is there or small white blobs appear on the surface.
Medicinally, decoctions are used externally for washing wounds and internally for curing aliments.
Decoctions are therapeutically more active as it vigorously extracts the virtues of medicinal plants, roots, twigs, barks and seeds.
Dose is 15-30 ml with water.
Infusion
Infusion is comparable to a cup of tea.
Boling or cold distilled water is poured on the drugs in a covered vessel and kept for fifteen minutes and then strained.
Sometimes boiling is done for hours to prepare strong infusion.
Hot infusion is stronger than cold as it extracts the active principle more effectively. Every drug has fixed time during which it imparts its property to water.
For preparing cold infusion boiling water is not required. Coarsely powered drug is kept in a closed vessel containing water for twenty–four waters. The powdered drug imbibes some liquid and a mass is formed. The mass is pressed to obtain liquid, which is collected in a measuring flask and mixed with water left in vessel and quantity is measured.
The infusions should be used within twelve hours until preservative has been added.
Sometimes infusions are prepared with weak alcohol which acts as preservative.
Shelf-life of alcohol based infusions has not been determined but it has advantage over water based infusions.
Water used in preparing infusions should be distilled. Hard water should not be used as uniform color is not obtained and it is not able to extract all the virtues of medicinal herbs.
Dose is 30-60 ml with water.
Powders
Powders are mixtures of dry substances reduced to fine powder and intimately mixed together. In Ayurvedic system of medicine, powdered preparations are known as churna-kalpna.
Drug to be powdered is thoroughly washed with water and dried. Properly dried drug is reduced to powder in a pestle and mortar.
Powders may be of a single substance and more often of several (compound powders). The different ingredients finely powdered separately and weighed to the required amount are carefully mixed with a spatula on a slab or with a small pestle and mortar and made in to fine, nearly impalpable form.
Powders should be mixed in a very clear mortar. The method of mixing greatly affects the miscibility of powders.
A powerful constituent should be first triturated with some bland substance and then slowly mixed with the rest of the lot. It should be packed in white glazed paper.
Hygroscopic drugs should be stocked in accurately fitting glass stoppered phials and dispensed wrapped in waxed or paraffin paper and preferably covered with tin foil.
A powered drug is made to pass through a sieve containing parallel wires closeness and powders of different fineness are produced
By repeated sifting and shaking in a bottle the ingredients are thoroughly incorporated and a uniformity of color is obtained.