Rule out other organic causes including substance abuse, medication effect or other medical conditions. Consider emergency psychiatric evaluation in addition to medical evaluation.
Point-of-care glucose
CBC
Chem 7
LFTs
ECG (for toxicology evaluation)
ASA level
Tylenol level
Urine toxicology screen/Blood toxicology screen
EtOH
Urine pregnancy/beta-hCG (if female of childbearing age)
Consider:
Ammonia (see Hepatic encephalopathy)
TSH (hypo or hyperthyroidism may mimic mental illness)
CXR (for Tb screen or rule-out delirium in older patient)
UA (for rule-out delirium in older patients)
Head CT (to rule-out ICH in patients with AMS)
Lumbar puncture (to rule-out meningitis or encephalitis)
Ammonia (see Hepatic encephalopathy)
TSH (hypo or hyperthyroidism may mimic mental illness)
CXR (for Tb screen or rule-out delirium in older patient)
UA (for rule-out delirium in older patients)
Head CT (to rule-out ICH in patients with AMS)
Lumbar puncture (to rule-out meningitis or encephalitis)
Delusional disorder
Acute psychosis
Borderline personality disorder
Schizophrenia
Dependent personality disorder
Schizoaffective disorder
Schizoid personality disorder
Paranoid personality disorder