Carbamazepine coma caused

A. Ataxia, nystagmus, ophthalmoplegia, movement disorders (dyskinesia, dystonia), mydriasis, and sinus tachycardia are common with mild to moderate overdose. With more serious intoxication, myoclonus, seizures (including status epilepticus), hyperthermia, coma, and respiratory arrest may occur. Atrioventricular (AV) block and bradycardia have been reported, particularly in the elderly. Based on Its structure similarity to tricyclic antidepressants, carbamazepine may cause QRS and QT interval prolongation and myocardial depression however, in case reports of overdose, QRS widening rarely exceeds 100-120 msec and Is usually transient. 

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