Conductimetric determination of methimazole

Methimazole, a thyroid inhibitor, is a weak acid. In this communication, its authentic powder and its tablets (Tapazole) are assayed via its acidic property in aqueous medium. The equivalence point is determined conductimetrically. The average percent recovery for its authentic powder and tablets were found to be 99.30 +/- 1.30 and 98.27 +/- 1.81 respectively. The method, proposed in this study, is simple, rapid and can be adopted for routine analysis in quality control laboratories.