A 45-year-old man with a history of epilepsy and psychiatric problems

A 45-year-old man with a history of epilepsy and psychiatric problems is admitted to the Emergency Department with confusion following a seizure earlier in the day. On examination he is noted to have a coarse tremor, blood pressure is 134/86 mmHg, pulse is 84/min and the temperature is 36.7ºC. What is the most likely diagnosis?

Carbamazepine overdose
Lithium toxicity
Benzodiazepine toxicity
Tricyclic overdose
Neuroleptic malignant syndrome