OBJECTIVE To compare the efficacy and safety of a homeopathic remedy (Vertigoheel, Heel Inc, Albuquerque, NM) vs betahistine hydrochloride (active control) in the treatment of patients with vertigo of various origins in a confirmative equivalence trial. METHODS Randomized (1:1) double-blind controlled clinical trial. METHODS Fifteen study centers (general practice) in Germany between November 1995 and November 1996. METHODS A total of 119 patients with vertigo of various origins (from whom 105 patients could be analyzed as intended per protocol). METHODS Frequency, duration, and intensity of vertigo attacks. RESULTS Both homeopathic and conventional treatments showed a clinically relevant reduction in the mean frequency, duration, and intensity of the vertigo attacks. The therapeutic equivalence of the homeopathic remedy and betahistine was established statistically. CONCLUSIONS Concerning the main efficacy variable, therapeutic equivalence between the homeopathic remedy and betahistine could be shown with statistical significance (confirmative analysis). Both remedies reduced the frequency, duration, and intensity of vertigo attacks during a 6-week treatment period. Also, vertigo-specific complaints were significantly reduced in both treatment groups.