title: Tinnitus treatment with piribedil guided by electrocochleography and acoustic otoemissions.
abstract: BACKGROUND
  Tinnitus is a frequent disorder and very difficult to treat. Both animal studies and clinical observations suggest that dopaminergic substances might have potential for the treatment of tinnitus. Here, we investigated the dopamine agonist piribedil for the treatment of chronic tinnitus. In all participants, we performed audiometry, electrocochleography (ECoG), and otoacoustic emissions before treatment began.
  
  
  OBJECTIVE
  To assess the efficacy and safety of the dopaminergic drug piribedil for the treatment of tinnitus and to evaluate whether ECoG and acoustic otoemissions might be useful for predicting treatment response.
  
  
  METHODS
  Prospective randomized double-blind crossover study.
  
  
  METHODS
  One hundred patients with tinnitus were randomized into a double-blind, placebo-controlled, prospective crossover study. All patients underwent distortion product acoustic otoemissions with and without contralateral suppression and ECoG. Patients received 50 mg piribedil and placebo for 90 days each, separated by a 30-day washout period. Treatment effects were assessed by using the Tinnitus Handicap Inventory and a visual analog scale. Fifty-six patients completed the trial.
  
  
  RESULTS
  There was no significant improvement of Tinnitus Handicap Inventory and visual analog scale score after piribedil treatment as compared with placebo. However, results were characterized by high interindividual variability. Post hoc analysis of piribedil effects revealed that piribedil treatment responders differed from nonresponders by the occurrence of a double peak in the ECoG. In addition, normal distortion product acoustic otoemission suppression patterns indicated better treatment response with piribedil. The incidence of side effects during piribedil treatment was 23.3%, leading to interruption of treatment in all cases.
  
  
  CONCLUSIONS
  Piribedil is not superior to placebo in the treatment of tinnitus. Piribedil treatment responders differed from nonresponders by specific findings in the ECoG and in the distortion product acoustic otoacoustic emissions, suggesting a beneficial effect of piribedil in an electrophysiologically characterized tinnitus subgroup.
authors: OTOSUL, Otorrinolaringologia Sul-Fluminense, Volta Redonda, Rio de Janeiro, Brazil. aaazevedo@otosul.com.br
authors: Andréia Aparecida
authors: AA
authors: de Azevedo
authors: Berthold
authors: B
authors: Langguth
authors: Patricia Mello
authors: PM
authors: de Oliveira
authors: Ricardo
authors: R
authors: Rodrigues Figueiredo
mesh_terms: D000368:Aged; D001300:Audiometry, Evoked Response; D018592:Cross-Over Studies; D015259:Dopamine Agents / Q000008:administration & dosage* / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology*; D010891:Piribedil / Q000008:administration & dosage* / Q000627:therapeutic use*; D014012:Tinnitus / Q000175:diagnosis / Q000188:drug therapy*
chemical_list: D015259:Dopamine Agents; D010891:Piribedil