Diagnostic criteria for serotonin syndrome
| Reproduced with permission from Radomski et al. Med Hypotheses 2000;55:218–24. | |
| • Increase in dosage or addition of a second serotonergic agent | |
| • Plus 4 major symptoms or 3 major and 2 minor symptoms | |
| Autonomic symptoms | |
| Major | Minor |
| Fever | Tachycardia |
| Hyperhidrosis | Tachypnoea, dyspnoea |
| Diarrhoea | |
| Hypo- or hypertension | |
| Mental symptoms | |
| Major | Minor |
| Confusion | Agitation, nervousness |
| Hypomania | Insomnia |
| Coma or altered consciousness | |
| Neurological symptoms | |
| Major | Minor |
| Rigidity | Akathisia |
| Myoclonus | Impaired coordination |
| Tremor | Mydriasis |
| Hyperreflexia | |
| • Exclusions | |
| No recent introduction or dose increase of neuroleptic | |
| Other causes (e.g. infective, metabolic, endocrine, toxic) excluded | |
| No similar symptoms attributed to psychiatric condition before introduction of serotonergic agent | |