Management of sodium-channel blocker poisoning: the role of hypertonic sodium salts.

Sodium-channel blockers act by slowing sodium influx into myocytes through voltage gated channels. Many substances have sodium-channel block- ing properties and many others show this effect when taken in overdose. Sodium-channel blocker poisoning, associat- ed with a high death rate, is characterized by a variety of clinical presentation, depending on the pharmaceutical agent involved. Sodium bicarbonate or lactate, increasing serum pH and extracellular concentration of the ion, displace the drug from its receptor sites and can be used for the treatment of cardiac toxicity in the setting of sodium-channel blocker poisoning. In spite of this theoretical assumption, the role played by hypertonic sodium salts is not well elucidated and conflicting results have been reported. Authors review the pathophysiologic mecha- nisms of sodium-channel blocker poisoning and the evidences in literature concerning the effica- cy of hypertonic sodium salts in the treatment of the related toxicity.