In 33 Menière patients (42 ears) the therapeutic effects of Dyazide (50 mg triamterene and 25 mg hydrochlorothiazide) were investigated in a cross-over placebo-controlled study. The hearing was measured by tone and speech audiometry whereas tinnitus and vertigo were recorded using fixed scales. In this study, Dyazide was found to have no significant effect on hearing or tinnitus. However, the vestibular complaints decreased significantly during the Dyazide treatment. Ears with a positive glycerol or furosemide test and ears with a fluctuating hearing loss did not show significant differences in hearing thresholds between the two periods in the trial. Of the 33 patients 17 had a distinct preference for Dyazide whereas 3 patients chose the placebo. The remaining 13 patients had no preference.