Comparative trial of thiacetazone with isoniazid and paraaminosalicyclic acid (PAS) with isoniazid in the treatment of pulmonary tuberculosis in Nigerians.

A comparative trial of a combination of thiacetazone 150 mg with isoniazid 300 mg in a once daily dose and that paraaminosalicyclic acid 12 gm uith isoniazid 300 mg daily in divided doses was carried out on 72 specially selected patients with pulmonary tuberculosis over a period of 12 months. The result of the trial showed that patients treated with thiacetazone/isoniazid combination responded equally favourably to therapy as the patients treated with PAS/isoniazid combination. The result of sputum conversion was similar in both groups. Radiological changes after treatment showed a significant similarity in both groups. It was observed that the thiacetazone/isoniazid combination is no more toxic than the PAS/isoniazid combination. There was no case of blood dyscrasia during the trial. Of the 72 patients who started the trial, a total of 19 (26 per cent) patients defaulted before the end of the third month. However, the remaining 53 patients (74 per cent) completed the trial, and the final analysis was based on this number. It was concluded that thiacetazone (150 mg/day) was of similar efficacy when compared with PAS (12 gm/day) as a companion drug for isoniazid (300 mg/day) in producing sputum conversion, and radiological changes in Nigerian tuberculosis patients and is therefore to be preferred because of its relative cheapness and once-a-day administration.