title: Compliance with azithromycin versus erythromycin in the setting of a pertussis outbreak.
abstract: BACKGROUND
  Erythromycin has traditionally been the choice for prophylaxis and treatment of pertussis, but recently azithromycin has been recommended as another first-line agent. We evaluated treatment adherence between exposed persons giving erythromycin or azithromycin during a community-wide pertussis outbreak.
  
  
  METHODS
  This was a case-control study. All cases and their contacts were prescribed either 56 doses of erythromycin over 14 days or 5 doses of azithromycin over 5 days. A standardized questionnaire regarding demographics, side effects, and compliance with therapy was administered by mail or telephone interviews.
  
  
  RESULTS
  Of 244 persons prescribed erythromycin, 139 (57%) completed the full course compared with 234 (93%) of 251 persons prescribed azithromycin (rate ratio [RR] 4.5; 95% confidence interval [CI], 2.9-7.0). The primary reason for not completing erythromycin was side effects in 79 (76%) persons, of whom 72 (91%) reported gastrointestinal upset, compared with azithromycin side effects in 6 (35%) of whom 5 (83%) reported gastrointestinal side effects.
  
  
  CONCLUSIONS
  Azithromycin was associated with significantly higher completion rates than erythromycin. Due to side effects, the use of azithromycin may be preferable to erythromycin in outbreaks of pertussis.
authors.affiliation: Infectious Diseases Division, Vanderbilt University School of Medicine, Nashville, TN 37232, USA. rose.devasia@vanderbilt.edu
authors.forename: Rose A
authors.initials: RA
authors.lastname: Devasia
authors.forename: Timothy F
authors.initials: TF
authors.lastname: Jones
authors.forename: Beth
authors.initials: B
authors.lastname: Collier
authors.forename: William
authors.initials: W
authors.lastname: Schaffner
mesh_terms: D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D017963:Azithromycin / Q000009:adverse effects / Q000627:therapeutic use*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004196:Disease Outbreaks; D004917:Erythromycin / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008297:Male; D055118:Medication Adherence; D014917:Whooping Cough / Q000188:drug therapy / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents; D004917:Erythromycin; D017963:Azithromycin