Objectives: Sulpiride and melatonin decrease dopamine activity. Sulpiride, a D2 antagonist of dopamine receptors, and melatonin, a pineal substance with antidopaminergic action, are administered to tinnitus patients to decrease tinnitus perception.
Design: A prospective, randomized, double-blinded, placebo-controlled study was done.
Setting: General otorhinolaryngologic consultation for 2002-2004 in Seville, Spain.
Methods: One hundred twenty patients consulted for subjective tinnitus. They were included randomly in four groups of 30. One group took sulpiride (50 mg/8 h) alone, the second group took melatonin (3 mg/24 h), the third group took the same doses of sulpiride (50 mg/8 h) plus melatonin (3 mg/24 h), and the fourth group took placebo (lactose 50 mg/8 h), all for 1 month. Ninety-nine patients completed the study.
Main outcome measures: Clinical history, tonal audiometry, tympanometry, and tinnitometry were done at the beginning and end of the study. Subjective grading of tinnitus perception and a visual analogue scale (0-10) were done for evaluation of results.
Results: Based on the subjective grading, tinnitus perception diminished by 56% in patients treated with sulpiride, by 40% in patients treated with melatonin, by 81% in patients treated with sulpiride plus melatonin, and by 22% in patients treated with placebo. Based on the visual analogue scale, tinnitus perception diminished from 7.7 to 6.3 in patients treated with sulpiride, to 6.5 in those treated with melatonin, to 4.8 in patients treated with sulpiride plus melatonin, and to 7.0 in those treated with placebo.
Conclusions: Sulpiride and melatonin reduce tinnitus perception, decreasing dopamine activity. The tinnitus auditolimbic dopaminergic pathway has broad therapeutic implications.