The drug, procainamide hydrochloride (NH2C6H4CONHCH2CH2N(CH2CH3)(2)HCl), was studied using a simultaneous thermogravimetric-differential thermal analysis unit (TG-DTA) in an atmosphere of nitrogen. The study covered the range of temperature from ambient to 800 degrees C. The DTA showed a melting point at 169 degrees C followed by a two stage endothermic transition. The TG-DTG plots clearly showed this two-stage transition. A kinetic analysis of the two stages was attempted. The best fit appeared to be a first order mechanism for both stages. It also was noted that the values of E-act varied as the reaction progressed. Supportive evidence regarding the study was obtained from a range of other physio-chemical measurements.