Altered mental status

DDx

Drugs

• Opioids, alcohol, sedatives, antipsychotics, withdrawal, others

Metabolic

• Hypoxia, hypoglycemia, hyperglycemia, hypercalcemia, hypernatremia, hyponatremia, uremia, hepatic encephalopathy, hypothyroidism, hyperthyroidism, vitamin B12 or thiamine deficiency, carbon monoxide poisoning, Wilson’s disease

Infectious

• Meningitis, encephalitis, bacteremia, urinary tract infection, pneumonia, neurosyphilis

Structural

• Space-occupying lesion, eg, brain tumor, subdural hematoma, hydrocephalus

Vascular

• Stroke, subarachnoid hemorrhage, coronary ischemia, hypertensive encephalopathy, CNS vasculitis, thrombotic thrombocytopenic purpura, disseminated intravascular coagulation, hyperviscosity

Psychiatric

• Schizophrenia, depression, mania

Other

• Seizure, nonconvulsive status epilepticus, hypothermia, heat stroke, ICU psychosis, "sundowning"