Table 2.
Condition | MedicationHistory | Time Needed for Condition to Develop | Vital Signs | Pupils | Mucosa | Skin | Bowel Sounds | Neuromuscular Tone | Reflexes | Mental Status |
---|---|---|---|---|---|---|---|---|---|---|
Serotonin syndrome | Proserotonergic drug | < 12 hr | Hypertension, tachycardia, tachypnea, hyperthermia (> 41.1°C) | Mydriasis | Sialorrhea | Diaphoresis | Hyperactive | Increased, predominantly in lower extremities | Hyperreflexia, clonus (unless masked by increased muscle tone) | Agitation, coma |
Anticholinergic “toxidrome” | Anticholinergic agent | < 12 hr | Hypertension (mild), tachycardia, tachypnea, hyperthermia (typically 38.8°C or less) | Mydriasis | Dry | Erythema, hot, and dry to touch | Decreased or absent | Normal | Normal | Agitated delirium |
Neuroleptic malignant syndrome | Dopamine antagonist | 1–3 days | Hypertension, tachycardia, tachypnea, hyperthermia (> 41.1°C) | Normal | Sialorrhea | Pallor, diaphoresis | Normal or decreased | “Lead-pipe” rigidity, present in all muscle groups | Bradyreflexia | Stupor, alert mutism, coma |
Malignant hyperthermia | Inhalational anesthesia | 30 min to 24 hr after administration of inhalational anesthesia or succinylcholine | Hypertension, tachycardia, tachypnea, hyperthermia (can be as high as 46.0°C) | Normal | Normal | Mottled appearance, diaphoresis | Decreased | Rigor mortislike rigidity | Hyporeflexia | Agitation |
From Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med. 2005;35:1112–1120, with permission.