Pal’s formula

The aim of this study is to present a Quick and Easy formula for the calculations of percent spike recovery of drug samples. Currently there are several cumbersome methods used in the determination of percent spike recovery in pharmaceutical analyses performed in various laboratories including the FDA laboratories around the world and especially in USA. In this paper we have compared the Quick & Easy Method using Pal’s formula against the method suggested by ORA Manual. The efficacy of this new formula has been demonstrated by seven examples including the main example of Pilocarpine hydrochloride discussed in detail. This Quick & Easy method is very simple, efficient and convenient way of determining percent spike recoveries and RPD values of duplicate spike solutions in drug analyses by HPLC, GC or UV methods. The simplicity of the method saves time and effort when compared to the existing method