Effect of Fasting on the Acute Toxicity of HI-6 and its Efficacy in Soman Poisoned Mice. Clement, John G. (1982). Fundam. Appl. Toxicol. 2:88-89. In rodents HI-6 is a very effective antidote of soman poisoning. After fasting, the IP LD50 value of HI-6 decreased from 660 mg/kg to 550 mg/kg. Fasting had no significant effect on the IV LD50 of HI-6. In fasted animals the ED50 for HI-6 (plus atropine) in soman toxicity decreased from 47.5 mg/kg to 14.8 mg/kg. Investigators should be aware of the nutritional status of the animals when comparing data between various laboratories.