Difference between revisions of "Serotonin syndrome"

(dexm added)
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''84% Sn, 97% Sp''
 
''84% Sn, 97% Sp''
  
==Treatment==
+
==Management==
 
*Discontinue all serotonergic drugs
 
*Discontinue all serotonergic drugs
 
*Aggressive supportive care
 
*Aggressive supportive care
Line 44: Line 44:
 
*[[Benzos]]
 
*[[Benzos]]
 
**Goal is to eliminate agitation, neuromuscular abnormalities, elevations in HR/BP
 
**Goal is to eliminate agitation, neuromuscular abnormalities, elevations in HR/BP
*Cyproheptadine<ref>Graudins, A., Stearman, A. and Chan, B. (1998) ‘Treatment of the serotonin syndrome with cyproheptadine’, The Journal of Emergency Medicine, 16(4), pp. 615–619. doi: 10.1016/s0736-4679(98)00057-2</ref>
+
*[[Cyproheptadine]]<ref>Graudins, A., Stearman, A. and Chan, B. (1998) ‘Treatment of the serotonin syndrome with cyproheptadine’, The Journal of Emergency Medicine, 16(4), pp. 615–619. doi: 10.1016/s0736-4679(98)00057-2</ref>
 
**Give if benzos and supportive care fail to improve agitation and abnormal vitals
 
**Give if benzos and supportive care fail to improve agitation and abnormal vitals
 
**Serotonin antagonist
 
**Serotonin antagonist
 
**Give 12mg PO/NG; repeat with 2mg q2hr until clinical response is seen (max 32mg/d)
 
**Give 12mg PO/NG; repeat with 2mg q2hr until clinical response is seen (max 32mg/d)
 
**Give 4mg q6hr x48hr if pt is responsive to initial dose
 
**Give 4mg q6hr x48hr if pt is responsive to initial dose
*Chlorpromazine<ref>Gillman PK. The serotonin syndrome and its treatment. J Psychopharmacol 1999;13:100-109</ref>
+
*[[Chlorpromazine]]<ref>Gillman PK. The serotonin syndrome and its treatment. J Psychopharmacol 1999;13:100-109</ref>
 
**Phenothiazine with antiserotonergic effects
 
**Phenothiazine with antiserotonergic effects
 
**50mg to 100mg IM
 
**50mg to 100mg IM
 
**Can consider in severe cases
 
**Can consider in severe cases
 +
*[[Dexmedetomidine]]<ref>Rushton WF, Charlton NP. Dexmedetomidine in the treatment of serotonin syndrome. Ann Pharmacother. 2014; 48(12):1651-1654.</ref>
 +
**Small case series found this helpful in adolescent cases refractory to benzos
 
*Treat hyperthermia
 
*Treat hyperthermia
 
**Hyperthermia due to increase in muscular activity, not change in set point
 
**Hyperthermia due to increase in muscular activity, not change in set point

Revision as of 13:31, 17 November 2015

Background

  • Can be produced by any serotonergic medication
  • Vast majority of cases occur with therapeutic dosages
  • Most common cause of death is severe hyperthermia

Causative Agents

  • SSRIs
  • MAOIs
  • TCAs
  • Drugs of Abuse: Cocaine, Ecstasy, Marijuana
  • Analgesics: Demerol, fentanyl
  • Antiemetics
  • Triptans
  • Bromocriptine
  • OTC: Cough meds like Dextromethorphan, herbal products, St John’s Wort

Clinical Features

  • Altered mental status: Agitated delirium
  • Autonomic Instability: Hyperthermia, Tachycardia, hypertension, diaphoresis [1]
    • Often labile blood pressure, HR
  • Neuromuscular Abnormalities: Myoclonus, ocular clonus, rigidity, hyperreflexia, tremor
    • More pronounced in the lower extremities
    • Myoclonus: most common finding
      • Important to identify because it does not occur in other conditions that mimic serotonin syndrome

Differential Diagnosis

Altered mental status and fever

Diagnosis

Hunter Toxicity Criteria Decision Rules

Serotonergic agent plus 1 of the following[2]:

  • Spontaneous clonus
  • Inducible clonus AND (agitation or diaphoresis)
  • Ocular Clonus AND (agitation or diaphoresis)
  • Tremor AND hyperreflexia
  • Hypertonia AND temp >38 AND (ocular clonus or inducible clonus)

84% Sn, 97% Sp

Management

  • Discontinue all serotonergic drugs
  • Aggressive supportive care
    • If pressors required, direct acting (e.g. norepi, epi) preferred, MAO inhibition causes erratic response to dopamine
  • Benzos
    • Goal is to eliminate agitation, neuromuscular abnormalities, elevations in HR/BP
  • Cyproheptadine[3]
    • Give if benzos and supportive care fail to improve agitation and abnormal vitals
    • Serotonin antagonist
    • Give 12mg PO/NG; repeat with 2mg q2hr until clinical response is seen (max 32mg/d)
    • Give 4mg q6hr x48hr if pt is responsive to initial dose
  • Chlorpromazine[4]
    • Phenothiazine with antiserotonergic effects
    • 50mg to 100mg IM
    • Can consider in severe cases
  • Dexmedetomidine[5]
    • Small case series found this helpful in adolescent cases refractory to benzos
  • Treat hyperthermia
    • Hyperthermia due to increase in muscular activity, not change in set point
    • Intubate and paralyze if temp > 41.1
    • Standard cooling measures

Disposition

See Also

References

  1. Boyer, E. W. and Shannon, M. (2005) ‘The Serotonin Syndrome’, New England Journal of Medicine, 352(11), pp. 1112–1120. doi: 10.1056/nejmra041867
  2. 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;96:635-642
  3. Graudins, A., Stearman, A. and Chan, B. (1998) ‘Treatment of the serotonin syndrome with cyproheptadine’, The Journal of Emergency Medicine, 16(4), pp. 615–619. doi: 10.1016/s0736-4679(98)00057-2
  4. Gillman PK. The serotonin syndrome and its treatment. J Psychopharmacol 1999;13:100-109
  5. Rushton WF, Charlton NP. Dexmedetomidine in the treatment of serotonin syndrome. Ann Pharmacother. 2014; 48(12):1651-1654.