title: Linezolid interaction with serotonin reuptake inhibitors: report of two cases and incidence assessment.
abstract: BACKGROUND
  Prompted by the advent of potentially life-threatening neuromuscular symptoms following initiation of linezolid therapy in two patients receiving treatment with a serotonin reuptake inhibitor antidepressant, an evaluation was conducted to determine the incidence and characteristics of symptomatic serotonin toxicity among hospitalized patients receiving combined treatment with these medications.
  
  
  METHODS
  Patients admitted between January 1, 2006 and August 30, 2008 who received linezolid concurrently with citalopram or escitalopram were identified and their medical records were examined. Patients were judged to have serotonin toxicity if their records contained documentation of clinical evidence adequate to fulfill requisites of the Hunter Serotonin Toxicity Criteria. Severity of serotonin-related symptoms was graded according to previously established criteria.
  
  
  RESULTS
  During the period of observation, 24 patients received concurrent treatment with linezolid and citalopram or escitalopram. Of these, one patient (4%) treated with citalopram met evidentiary requirements for diagnosis of serotonin toxicity. The severity of symptoms in this patient was graded as mild. No evidence of serious harm related to a possible drug interaction was identified.
  
  
  CONCLUSIONS
  Severe symptoms associated with serotonin toxicity were shown to be uncommon in patients receiving linezolid and selected serotonin reuptake inhibitors. Nonetheless, serious interaction-related toxicity has been observed at our institution and reported in detail by others. Accordingly, concurrent use of these medications is categorized as contraindicated. Alternative antimicrobial therapy should be instituted in most cases. If no suitable alternative is available, recipient patients should be hospitalized for expectant observation and rigorous monitoring.
authors.affiliation: University of Colorado Hospital, Aurora, CO 80045-2515, USA.
authors.forename: Amy C
authors.initials: AC
authors.lastname: Go
authors.forename: Larry K
authors.initials: LK
authors.lastname: Golightly
authors.forename: Gerard R
authors.initials: GR
authors.lastname: Barber
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Barron
mesh_terms: D000081:Acetamides / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D000890:Anti-Infective Agents / Q000008:administration & dosage* / Q000009:adverse effects* / Q000627:therapeutic use; D015283:Citalopram / Q000009:adverse effects / Q000627:therapeutic use; D004347:Drug Interactions; D005260:Female; D006801:Humans; D000069349:Linezolid; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus; D008875:Middle Aged; D023303:Oxazolidinones / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use; D010146:Pain / Q000209:etiology; D020230:Serotonin Syndrome / Q000453:epidemiology* / Q000523:psychology; D017367:Selective Serotonin Reuptake Inhibitors / Q000008:administration & dosage / Q000009:adverse effects*; D020280:Sertraline / Q000009:adverse effects; D013203:Staphylococcal Infections / Q000150:complications / Q000188:drug therapy; D014202:Tremor / Q000139:chemically induced
chemical_list: D000081:Acetamides; D000890:Anti-Infective Agents; D015283:Citalopram; D000069349:Linezolid; D023303:Oxazolidinones; D017367:Selective Serotonin Reuptake Inhibitors; D020280:Sertraline