TABLE 17.5 POISONS UNDETECTED BY TYPICAL DRUG SCREENING THAT CAUSE COMA/ALTERED LEVEL OF CONSCIOUSNESS Miosis present Bromide Chloral hydrate Clonidine Gamma-hydroxybutyrate (GHB) Methadone, buprenorphine Organophosphates Phenobarbital Pilocarpine and tetrahydrozoline eye drops Phenothiazines Valproic acid Mydriasis present Anoxia caused by cyanide, carbon monoxide, or methemoglobinemia LSD A toxicologic screen of blood and urine should be considered in all children with coma of unknown origin The growing legality and popularity of edible marijuana preparations has produced a rise in pediatric cannabis ingestions causing ALOC Table 17.5 lists compounds capable of causing coma that are not typically detected by routine drug screening, grouped by pupillary effects The poisoned patient with depressed consciousness should be intubated with a cuffed endotracheal tube for airway protection Naloxone may be administered as empiric antidotal therapy for coma-producing toxic ingestions involving unknown medications Flumazenil should not be given routinely to these patients because seizures may result Its use is limited to pure benzodiazepine overdoses in patients with no history of seizures or drug habituation Increased Intracranial Pressure or Focal Neurologic Defect Nontraumatic causes of increased ICP or focal neurologic deficits include neoplasms, CSF shunt malfunction, cerebral abscess, and hemorrhage (see Chapters 97 Neurologic Emergencies and 122 Neurosurgical Emergencies )