Local heat and cold application after eastern cottonmouth moccasin (Agkistrodon piscivorus) envenomation in the rat: effect on tissue injury.

We studied the effect of local application of heat or cold on the development of tissue necrosis in envenomated rats. Anesthetized animals had 6 mg/kg venom from Agkistrodon piscivorus injected subcutaneously into the lateral aspect of a hind limb. Heat or cold was applied to the site of envenomation in the experimental groups for 4-6 hr, and the injected area was examined histologically after 24 hr. Neither local treatment, with or without the presence of systemic antivenin, significantly affected the severity of tissue necrosis induced by the venom in comparison to a control group left at ambient temperature.