| Spontaneous clonus |
| Inducible clonus plus agitation or diaphoresis |
| Ocular clonus plus agitation or diaphoresis |
| Tremor plus hyperreflexia |
| Hypertonia plus temperature above 38 |
Table 64.2. Serotonin syndrome (SS) vs. neuroleptic malignant syndrome (NMS)
| SS | NMS | |
|---|---|---|
| Onset | 24 hours | Days to weeks |
| Precipitating medications | Serotonergic agents (e.g., SSRIs, MAOIs, meperidine, linezolid, psychoactive drugs of abuse) | Antipsychotics (e.g., phenothiazines, butyrophenones, thioxanthines) |
| Mechanism of action | Stimulation of serotonin receptors | Dopamine blockade |
| Neuromuscular abnormality | Clonus | Rigidity |
| Specific treatment | Cyproheptadine | Bromocriptine |
MAOI, monoamine oxidase inhibitor. SSRI, selective serotonin re-uptake inhibitor.
Full access? Get Clinical Tree

