Characteristics of the thermal decomposition of antituberculous drugs

The thermal decomposition of antituberculous drugs-ethambutol (base and dihydrochloride), isoniazid, ethionamid and pyrazinamid has been studied by DTA, TG and DTG techniques. General remarks have been made on their thermal destruction. The effect of sample size over the range 20–200 mg and heating rate over the range 3–15 deg·min^?1 on the thermal degradation has also been investigated. Moreover, based on the Kissinger’s equation, the values of the kinetic parameters were determined.