A triple blind, placebo controlled, randomised controlled trial of betahistine dihydrochloride in the treatment of primary tinnitus.

ABSTRACT

OBJECTIVES: To evaluate the effectiveness of betahistine in the treatment of primary tinnitus. DESIGN: To evaluate the effectiveness of betahistine in the treatment of primary tinnitus. SETTING: Universidade estadual Paulista Julio de Mesquita Filho, Botucatu Medical School, São paulo, Brazil. PARTICIPANTS: Adult patients with primary tinnitus who had not undergone treatment for tinnitus in the last 6 months were included. Patients with profound sensorineural deafness, hearing aid users and patients with metabolic, neurological, psychiatric or decompensated cardiovascular diseases were excluded. STUDY GROUPS in the betahistine group, patients received betahistine 24 mg every 12 h for 90 days; in the control group, patients received placebo tablets every 12 h for 90 days. MEAN OUTCOME MEASURES: Primary outcome measure: Tinnitus Handicap Inventory (THI). SECONDARY OUTCOME MEASURES: Clinical Global Impression Improvement (CGI-I) and a question of 'Yes' or 'No' to participants about their perception of improvement in symptoms. RESULTS: Of 284 participants initially identified, 62 were randomised (betahistine group n = 31; control group n = 31). Median age (IQR) 54 (48-60) years, with a balanced number of men and women. There was no difference in THI outcome between the study groups (median difference, -2 points; 95% CI, -8 to 6 points); the THI after the intervention was a median (IQR) 4 (-4 to 14) lower points in the betahistine group, and a median (IQR) 2 (-6 to 10) in the control group. There was no statistical difference in secondary outcome measures. Adverse events were mild and there was no statistical difference between groups. CONCLUSIONS: Betahistine dihydrochloride was ineffective in the treatment of primary tinnitus in adults.