see also: [[Sodium channel blocker]] > [!important] Key Points > - **risk_dose**:: \> 20mg/kg risk dose ; death doses >4g > - **Antidote**:: MDAC, +/- haemodialysis > - **key_points**:: # Risk assessment - \> 20mg/kg risk dose - death doses >4g # Toxic Mechanism - blocks Na and Ca channels, dopamine inhibition, NA and serotonin reuptake, reversible MAOI - sodium-channel blockage poorly responsive to HCO3 # Clinical features CNS - nstagmus, ataxia, intractable [[Seizures#Toxicological Seizures|seizures]] CVS - wide QRS (sodium-channel blockade), ventricular arrhythmias  # Treatment - charcoal +/- [[Decontamination#Dose for MDAC|MDAC]] - [[haemodialysis]] if >4g + QRS prolongation, arrhythmias, intractable seizures  - HCO3 doesn't usually fix problem - ==avoid beta blockers and amiodarone== - maintain normal K, Mg, and Ca # Disposition if asymptomatic at 6 hours can d/c