serotonin syndrome

 Q: In serotonin syndrome, bowel sounds tend to be? (select one)

A) hypoactive

B) hyperactive

Answer: B

The objective of this question is to emphasize the importance of physical exam in serotonin toxicity which may be the only clue besides history. In contrast to opioid toxicity, serotonin syndrome tends to have a hyperactive state of body functions including increase bowel sounds on abdominal auscultation. Other important signs include:

• tachycardia 
• dramatic swings in blood pressure
• dramatic swings in pulse 
• hyperthermia
• agitation 
• ocular clonus
• dilated pupils 
• tremor 
• akathisia 
• deep tendon hyperreflexia 
• muscle clonus and rigidity 
• positive Babinski signs 
• dry mucus 
• flushed skin 
• diaphoresis 

#toxicology

References:

1. Boyer EW, Shannon M. The serotonin syndrome. N Engl J Med 2005; 352:1112. 

2. Birmes P, Coppin D, Schmitt L, Lauque D. Serotonin syndrome: a brief review. CMAJ 2003; 168:1439. 

3. Mason PJ, Morris VA, Balcezak TJ. Serotonin syndrome. Presentation of 2 cases and review of the literature. Medicine (Baltimore) 2000; 79:201.