Evaluation of botulinum toxin A in treatment of tinnitus.
OBJECTIVE
The purpose of this study was to evaluate the potential benefit of botulinum toxin A in treatment of tinnitus with a prospective, double-blinded study design.


METHODS
Double-blinded, prospective clinical study.


METHODS
Thirty patients with tinnitus were randomly placed into 1 of 2 treatment arms. Patients either received botulinum toxin A (20 to 50 units) or saline injection at the first treatment, and the opposite treatment 4 months later. Prospective data including tinnitus matching test, tinnitus handicap inventory (THI), tinnitus rating scale (TRS), and patient questionnaires were obtained over a 4-month period after each injection.


RESULTS
Twenty-six patients completed both injections and follow-up and were included in data analysis. After botulinum toxin A, subjective tinnitus changes included 7 patients improved, 3 worsened, and 16 unchanged. Following placebo, 2 patients were improved, 7 worsened, and 17 unchanged. Comparison of the treatment and placebo groups was statistically significant (P < 0.005) when including better, worse, and same effects. A significant decrease in THI scores between pretreatment and 4 month postbotulinum toxin A injection (P = 0.0422) was recorded. None of the other comparisons of pretreatment to 1 month, or pretreatment to 4 months were significantly different.


CONCLUSIONS
This small study found improvement in THI scores and patient subjective results after botulinum toxin A injection compared with placebo, suggesting a possible benefit of botulinum toxin A in tinnitus management. Larger studies need to be completed to further evaluate potential benefits of botulinum toxin A in treatment of this difficult problem.
Stidham
Katrina R
KR
California Ear Institute, San Ramon, CA 94583, USA. krs@calear.com
Solomon
Perry H
PH
Roberson
Joseph B
JB
D000328:Adult; D000368:Aged; D019274:Botulinum Toxins, Type A / Q000627:therapeutic use*; D004311:Double-Blind Method; D006801:Humans; D008875:Middle Aged; D009465:Neuromuscular Agents / Q000627:therapeutic use*; D011446:Prospective Studies; D014012:Tinnitus / Q000188:drug therapy*
D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A