Usually will not be diagnosed in the emergency department
Needs evaluation by a psychiatrist
Rule out alternative medical explanation for symptoms, as appropriate
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)
Meets criteria for one manic or mixed episode
Symptoms cause social/occupational distress or impairment
Meets criteria for at least one major depressive episode
Meets criteria for at least one hypomanic episode
Does not meet criteria for manic or mixed episode
Symptoms cause social/occupational distress or impairment<unk>  with<unk>  features that do not meet criteria for specific<unk>
Bipolar disorder
Organic causes
Depression
Delirium
Alcohol use disorder
Dementia
Schizoaffective disorder
Overdose