Clinical Manifestation and Prognostic Factors of Chronic Dizziness Due to Long-Term Use of Vestibular Suppressant

Abstract

Background and Objectives Dimenhydrinate and benzodiazepine are widely used for the prevention of nausea and vomiting in a variety of acute vestibular diseases. Due to the prolongation of central compensatory mechanism and dependency, the long-term use of vestibular suppressants can elicit various atypical vestibular symptoms and vestibular function test (VFT) results, which result in neglect and underdiagnosis. This study aimed to investigate the effect of long-term use of vestibular suppressants and identify significant prognostic factors.Subjects and Method Thirty-two patients diagnosed with vestibular suppressant drug associated dizziness (DAD) were enrolled. The patients were instructed to discontinue the suppressants and undergo vestibular rehabilitation therapy. The severity of dizziness, compliance to treatment, prognosis, and the results of VFT were evaluated.Results Most of the patients (65.6%) complained of spinning vertigo while some of the patients (25.0%) complained of unsteadiness, directional pulsion, or non-vertiginous dizziness, making the diagnosis difficult. The severity of the DAD symptoms was dependent on the preceding vestibular disorder: it was significantly milder when the preceding vestibular disorder was benign paroxysmal positional vertigo. Atypical findings of VFT that cannot be fully explained based on known vestibular disorders were frequently observed (9.4%-54.5%). Preceding vestibular disorders of old age, non-compliance with vestibular rehabilitation and vestibular neuritis were found to be independent bad prognostic factors.Conclusion Understanding and being aware of DAD as a cause of dizziness may help patients suffering from chronic dizziness without a certain diagnosis.