Title: Serotonin Syndrome (Part 1) - What is It? <br/>Author: Wan-Tsu Wendy Chang<br/><a href='http://umem.org/profiles/faculty/1322/'>[Click to email author]</a><hr/><p>
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<strong>Serotonin Syndrome - What is It?</strong></p>
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Potentially life-threatening condition associated with increased serotonergic activity in the CNS.</li>
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Selective serotonin reuptake inhibitors (SSRIs) are the most commonly implicated class of medications. However, other medications can also be involved.</li>
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<strong>It is a clinical diagnosis!</strong></li>
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<u>Classic triad</u>: mental status change, autonomic hyperactivity, and neuromuscular abnormalities
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<u>Mental status change</u> - anxiety, agitation, restlessness, disorientation</li>
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<u>Autonomic hyperactivity</u> - diaphoresis, tachycardia, hypertension, hyperthermia, nausea, vomiting, diarrhea</li>
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<u>Neuromuscular abnormalities</u> - tremor, muscle rigidity, myoclonus, hyperreflexia, clonus, Babinski sign (abnormal plantar reflex)</li>
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Hunter Criteria is the most accurate diagnostic rule:
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Serotonergic agent + one of the following:
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Spontaneous clonus</li>
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Inducible clonus <em>+</em> agitation or diaphoresis</li>
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Ocular clonus <em>+</em> agitation or diaphoresis</li>
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Tremor <i>+</i> hyperreflexia</li>
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Hypertonia + temperature above 38C + ocular clonus or inducible clonus</li>
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Majority of cases present within 24 hours, most within 6 hours, of a change in dose or initiation of a medication.</li>
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<em>** Stay tuned for part 2 on what causes serotonin syndrome **</em></p>
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<fieldset><legend>References</legend>
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Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med. 2005;352:1112-1120.</li>
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Dunkley EJ, Isbister GK, Sibbritt D, Dawson AH, Whyte IM. The Hunter Serotonin Toxicity Criteria: simple and accurate diagnostic decision rules for serotonin toxicity. QJM. 2003;96(9):635.</li>
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