The dependence of the blood level of the oxime HS-6 on the severity of organophosphate poisoning.

Atropinised anaesthetised rats were injected i.v. with 4, 6 or 8 X LD50 of the organophosphorous anticholinesterase soman. Subsequent treatment with one dose of HS-6 (100 mg/kg, i.v.) delayed respiratory failure by 1 h or more; a further postponement was obtained when an additional HS-6 infusion was given. At the same infusion rate, HS-6 blood levels after 4 X LD50 soman remained stationary, but rose after the higher soman doses. The rise was greater the higher the soman dose had been. This rapid rise in oxime blood levels after high doses of organophosphate may seriously complicate therapy.