Churna, Vati, Kwatha, Taila and Arishta: Forms of Ayurvedic Preparations

Why the form matters

An Ayurvedic medicine is the plant or mineral plus the form it is made into. Ayurveda has a whole sub-discipline devoted to drug formulation, called bhaishajya kalpana. A review of it explains that Ayurvedic drug formulation rests on the "pancavidha kashaya" concept of five basic forms, with many other forms derived from them. [1] The form affects how long a product keeps, how it is tested, and what the main quality worries are. This page describes forms in general terms. It gives no recipes or preparation steps, and home preparation of mineral or metal products is never advised.

The common forms

Oils and ghee have their own page: medicated oils and ghee in Ayurveda.

Shelf life

Classical texts gave shelf lives by form. A review table drawn from the Sharangadhara Samhita lists powder as two months, tablets, pills and syrups as one year, and medicated oil and ghee as sixteen months. [8] That is a traditional rule of thumb, not a laboratory result.

Modern Indian rules are different. A 2016 amendment to the Drugs and Cosmetics Rules requires that the date of expiry of Ayurvedic, Siddha or Unani medicines be conspicuously displayed on the label. [9]

A review of kwatha dosage forms notes that kwatha (decoction) has a short shelf life, takes time to prepare and is unpalatable, which limits its use. [10] The authors say it can be converted into longer-lasting forms such as tablets, granules, syrup and arishta. [11] Their claim that efficacy is largely kept comes from review of texts, not from head-to-head human trials. In the sources we read, Proper evidence not found that one form works better than another.

How the forms are tested

India's Central Council for Research in Ayurvedic Sciences publishes guideline test lists by form. For powders and for tablets and pills the list includes tests for lead, cadmium, mercury and arsenic, pesticide residue, microbial contamination, specific pathogens and aflatoxins. [12] [13] The list for fermented liquids includes alcohol content, a test for methanol and a test for heavy or toxic metals. [14] [15] The list for medicated oils and ghee includes rancidity, peroxide value, a mineral oil test (which should be negative) and heavy metals. [16] [17] [18] [19]

These are guideline test lists for manufacturers, so they show what a good product should be checked for. They do not show that a given product on a shelf passed them. More on the standards is on the pharmacopoeia and standards page.

Fermented preparations and alcohol

In asava and arishta the alcohol that forms during fermentation acts as a self-preservative. [20] Measured amounts vary. A Sri Lankan study of 12 samples of three arishta, from four manufacturers, found ethanol between about 5.8 and 8.4% by volume, [21] and no stimulants or anabolic steroids banned in sport. [22] An Indian study of 20 over-the-counter fermented formulations from three manufacturers [23] found significant differences in ethanol content [24] and concluded that the data reflected poor compliance with good manufacturing practice. [25] If you avoid alcohol for medical, religious or recovery reasons, or are pregnant or choosing for a child, ask a clinician or pharmacist before using an arishta.

Contamination and mislabeling in any form

Form does not protect against contamination. Testing of Ayurvedic products found lead, mercury or arsenic in about one in five products bought online. [26] NCCIH warns that some preparations may contain these metals in amounts that can be toxic. [27] See heavy metals and product quality. A published case report describes a patient who took Ayurvedic powder medicine alongside a gold-containing bhasma and had worsening liver injury. [28]

Related pages

• Ayurvedic herbal preparations: the overview
• Product quality and contamination