Recent Advances In Treatment of Acute Organophosphorous Nerve Agents Poisoning

Organophosphorous (OP) chemical warfare nerve agents mainly sarin and tabun were used during the Iran-Iraq war with high mortalities. In addition to atropine and oximes, the followings have recently been used successfully for the treatment of OP poisoning. 1. Sodium Bicarbonate: Infusion of high doses of sodium bicarbonate (5 mEq/kg in 60 min. followed by 5-6 mEq/kg/day to obtain arterial blood pH of 7.45 to 7.55) revealed positive effects in patients with acute OP poisoning in Mashhad. 2. Magnesium Sulfate: Intravenous magnesium sulfate in a dose of 4 g only on the first day after admission was also effective in acute human OP poisoning. 3. Antioxidants: The toxicity of OP compounds is mediated by generation of nitric oxide and other free radicals. These toxic molecules can be counteracted by antioxidants such as vitamins C and E, spin traps, melatonin and low molecule weight thiols. The latter compounds can also increase the synthesis of glutathione, which can both ameliorate the OP-induced oxidative stress and enhance OP detoxification. It is concluded Sodium bicarbonate, Magnesium sulfate and the antioxidants should be added to the standard treatment of OP poisonings.