Isoniazid pharmacokinetics in patients in chronic renal failure.

INH pharmcokinetics was studied in 2 groups of patients in chronic renal failure. In the group on conservative treatment, INH half life was prolonged, but was not related to the degree on renal impairement. In the hemodialysis group 73% of the INH given was removed by dialysis within 5 hours. If INH is to be used in the presence of renal failure, individual half life estimations should be performed in order to determine dosage frequency. In patients on hemodialysis, therapy should be given post dialysis. Alternatively, drugs not dependent on renal failure, e.g. rifampicin, may be preferable.