TOXICITY OF ISONICOTINIC ACID HYDRAZIDES IN PULMONARY TUBERCULOSIS

Abstract

INFORMATION available at the present time concerning the toxicity of isoniazid (isonicotinic acid hydrazide) has shown it to be a relatively safe agent for the treatment of pulmonary tuberculosis.* Although a variety of side-effects have been observed, the majority of these have been of minor importance. However, several reports have drawn attention to occasional severe reactions, in particular, psychoses,† peripheral neuritis,‡ hemoptyses,⁶ and pellagra.⁷ Furthermore, experience with iproniazid has shown it to be considerably more toxic than isoniazid.¹ At Trudeau Sanatorium the use of iproniazid for investigation has recently been terminated because of frequent and sometimes severe side-effects, as compared to those observed with isoniazid. Documentation of the specific toxicity observed with each of these drugs, both alone and in combination with streptomycin or^p-aminosalicylic acid (PAS), is important for comparison with present and future chemotherapeutic agents. This report presents data on the incidence of side-effects and causes of termination of