title: Acyclovir is not effective in pityriasis rosea: Results of a randomized, triple-blind, placebo-controlled trial.
abstract: BACKGROUND
  Acyclovir is considered to be an effective treatment for pityriasis rosea but randomized, blinded, placebo-controlled trials have not been performed.
  
  
  OBJECTIVE
  To test the efficacy of acyclovir in pityriasis rosea in a randomized, triple-blind, placebo-controlled trial.
  
  
  METHODS
  Twenty seven patients with pityriasis rosea were randomly allocated to receive placebo (n = 13) or acyclovir (800 mg five times daily for one week) (n = 14). The severity of disease was assessed by the pityriasis rosea area and severity index. Cure was defined as the absence of erythema, with no or minimal scaling.
  
  
  RESULTS
  The number of days (mean ± standard deviation) taken for cure was not significantly different between the two groups (placebo 26.54 ± 9.14 days versus acyclovir 33.29 ± 9.49 days; P = 0.0720, t-test; 95% confidence interval of difference -0.65 to 14.14 days).
  
  
  CONCLUSIONS
  The sample size for the present study was calculated using data from an earlier study. As the standard deviation was not mentioned in that article, a common standard deviation of fifteen days was assumed. A study with a larger sample size may be more effective in detecting minor treatment differences between acyclovir and placebo, if they exist at all.
  
  
  CONCLUSIONS
  Acyclovir is not an effective treatment for pityriasis rosea.
authors.affiliation: Department of Dermatology and Venereology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Singh
authors.affiliation: Department of Community Medicine, Government Medical College, Kannauj, Uttar Pradesh, India.
authors.forename: Narendra K
authors.initials: NK
authors.lastname: Tiwary
mesh_terms: D000212:Acyclovir / Q000627:therapeutic use*; D000293:Adolescent; D000328:Adult; D000998:Antiviral Agents / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D017515:Pityriasis Rosea / Q000175:diagnosis* / Q000188:drug therapy*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000998:Antiviral Agents; D000212:Acyclovir