RESUMO
The polymeric anti-tubercular drug systems "Biophthizoetham-K" and "Biophthizoetham-P" have been obtained by chemical modification of parent compounds isoniazid and ethambutol with carboxymethilcellulose and polygalacturonic acid. These systems were less toxic then the parent compounds; they exhibited prolonged anti-tubercular action at a dose sixfold lower than isoniazid. Pharmacokinetic studies have shown that after administration of "Biophthizoetham-K" and "Biophthizoetham-P", therapeutic concentration of active substances (isoniazid and ethambutol) in blood remained longer than after administration of active substances alone. Introduction of isoniazid in the polysaccharide matrix decreased its metabolism into the therapeutically inactive form--acetilizoniazid.