OBJECTIVE: Low-frequency repetitive transcranial magnetic stimulation (rTMS) has shown promise for the treatment of tinnitus. Experimental data from motor cortex stimulation in healthy subjects indicate that the suppressing effect of low-frequency rTMS can be enhanced by dopaminergic receptor activation. Here we investigated whether administration of the dopamine precursor levodopa before low-frequency rTMS enhances its efficacy in tinnitus treatment.
STUDY DESIGN: Sixteen patients with chronic tinnitus received 100 mg of levodopa before each session of low-frequency rTMS. Results were compared with a matched control group of 16 patients who received the same treatment, but without levodopa. Treatment outcome was assessed with a standardized tinnitus questionnaire.
RESULTS: Both stimulation protocols resulted in a significant reduction of tinnitus scores after 10 days of stimulation; however, there was no significant difference between the two groups.
CONCLUSION: Our data suggest that 100 mg of levodopa does not enhance the effect of rTMS in the treatment of tinnitus.
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