An overview of the causes of current practices in Pratinidhi Dravyas (substitution of drugs) in Ayurveda including newer techniques for their evaluation.

Many Pratinidhi Dravyas in Ayurvedic classics are mentioned and certainly are based on a methodical approach, which involves many aspects. These principles on which Pratinidhis were decided are quoted nowhere; so both to understand the established Pratinidhis and to find new ones a rational approach is the need of the hour. This article is an effort in the direction to study this concept meticulously in light of modern techniques for its better understanding and application. As there are very few established parameters, which help for selection and evaluation of Pratinidhi Dravyas. A rational technique like Fourier transform infrared spectroscopy may be incorporated to set a new dimension. As most of the routine analytical techniques are separation based, overall component load cannot be predicted. Thus, it is prime necessity to compare the drugs with a whole aspect, which goes in hand by hand with a holistic approach of Ayurveda "Treat the man as Whole -- Take the drug as whole." [ABSTRACT FROM AUTHOR]