Tumor Primary CNS tumor Metastatic CNS tumor Leukemic or carcinomatous meningitis Hyperleukocytosis Infection Meningitis—bacterial, fungal Viral encephalitis Brain abscess Septic shock Cerebrovascular accident Seizure/postictal state Increased intracranial pressure Shunt malfunction All transretinoic acid (Tretinoin) Cytotoxic chemotherapy Methotrexate Cytosine arabinoside Ifosfamide Thalidomide Supportive care Opiates Benzodiazepines Gabapentin Anticonvulsants Tricyclic antidepressants Antihistamines Dronabinol Leukoencephalopathy Metabolic derangements Hyponatremia/SIADH Hypo/hyperglycemia Hypomagnesemia Uremia Postradiation therapy somnolence syndrome Hypo/hypertension Hypoxia Liver failure