THE SPUTUM LEVELS OF ISONIAZID AFTER ORAL ADMINISTRATIONS

Abstract

The lst Department of Internal Medicine, Kumamoto University, Medical School
The sputum levels of isoniazid after oral administrations were estimated by the modified one of Dr. Mandel's bioassay after the homogenization of samples with papain digestion and decontamination with heating.
The sputum INH levels were in most cases lower than the serum levels of the same cases, that is, the formers were half or quarter of the latters showing 0.2mcg/ml 2 to 6 hours after administration of 200mg.
After giving 200mg of INH in three divided dosages the sputum levels were 0.1mcg/ml or less in more than 80% of cases.
No remarkable rise of the sputum levels was obtained by the increased dosage of INH in 300mg or 600mg.
The maximal INH levels in sputum were slightly later than those in serum, disappearing after 8 to 10 hours.
The higher INH sputum levels were observed in the cases with recent origin, especially with cavities with non-sclerotic wall.
As sputum, the softend caseous or purulent substances in the resected pulmonary or renal tuberculous lesions showed the lower INH levels than the serum.
The increases of sputum INH levels were obtained by the combined use of Depot Kallikrein, Antigene methylique or old tuberculin in most cases.
Indeed, the improvements of X-grams or the conversions of tubercle bacilli in the sputum were observed in the most cases treated combined with old tuberculin or Antigene methylique.