Consult psychiatry
"Benzodiazepine challenge" (first-line treatment)
Lorazepam IV 2mg; repeat prn
60-70% of patients will achieve remission with benzodiazepine monotherapy
Second line treatment is electro-convulsive therapy (ECT)
80-100% effective
Lorazepam IV 2mg; repeat prn
60-70% of patients will achieve remission with benzodiazepine monotherapy
80-100% effective
Avoid antipsychotic medications, as they may worsen symptoms
Catatonia
Hypoxic encephalopathy
Dysphonia
Acute toxic-metabolic encephalopathy 
Opsoclonus
Hypoglycemia
Tremor
Hyperosmolar state 