Common Etiologies of Delirium
| Toxins |
| Prescription medications: especially those with anticholinergic properties, narcotics, and benzodiazepines |
| Drugs of abuse: alcohol intoxication and alcohol withdrawal, opiates, ecstasy, LSD, GHB, PCP, ketamine, cocaine, “bath salts,” marijuana and its synthetic forms |
| Poisons: inhalants, carbon monoxide, ethylene glycol, pesticides |
| Metabolic conditions |
| Electrolyte disturbances: hypoglycemia, hyperglycemia, hyponatremia, hypernatremia, hypercalcemia, hypocalcemia, hypomagnesemia |
| Hypothermia and hyperthermia |
| Pulmonary failure: hypoxemia and hypercarbia |
| Liver failure/hepatic encephalopathy |
| Renal failure/uremia |
| Cardiac failure |
| Vitamin deficiencies: B12, thiamine, folate, niacin |
| Dehydration and malnutrition |
| Anemia |
| Infections |
| Systemic infections: urinary tract infections, pneumonia, skin and soft tissue infections, sepsis |
| CNS infections: meningitis, encephalitis, brain abscess |
| Endocrine conditions |
| Hyperthyroidism, hypothyroidism |
| Hyperparathyroidism |
| Adrenal insufficiency |
| Cerebrovascular disorders |
| Global hypoperfusion states |
| Hypertensive encephalopathy |
| Focal ischemic strokes and hemorrhages (rare): especially nondominant parietal and thalamic lesions |
| Autoimmune disorders |
| CNS vasculitis |
| Cerebral lupus |
| Neurologic paraneoplastic syndromes |
| Seizure-related disorders |
| Nonconvulsive status epilepticus |
| Intermittent seizures with prolonged postictal states |
| Neoplastic disorders |
| Diffuse metastases to the brain |
| Gliomatosis cerebri |
| Carcinomatous meningitis |
| CNS lymphoma |
| Hospitalization |
| Terminal end-of-life delirium |
Abbreviations: GHB, 𝛄-hydroxybutyrate; LSD, lysergic acid diethylamide; PCP, phencyclidine.