By Louise M. Klebanoff, MD
Assistant Professor of Clinical Neurology, Weill Cornell Medical College
In a meta-analysis of published studies of treatment of acute vertigo, the authors concluded that treatment with an antihistamine is more effective than benzodiazepines for the acute symptoms. However, there was no difference between the two medications in terms of resolution within one week or within one month.
Hunter BR, Wang AZ, Bucca AW, et al. Efficacy of benzodiazepines or antihistamines for patients with acute vertigo: A systematic review and meta-analysis. JAMA Neurol 2022; Jul 18. doi:10.1001/jamaneurol.2022.1858. [Online ahead of print].
Vertigo is a common and frequently disabling sensation of movement that can affect up to 20% of the adult population, with an increasing incidence with age and a higher prevalence among women. The etiology of acute vertigo includes benign paroxysmal positional vertigo (BPPV), vestibular neuronitis, Ménière’s disease, vestibular migraine, and stroke, among others. Treatment can be tailored to the specific cause of vertigo, especially with repositioning techniques used for BPPV.
However, persistent complaints of dizziness often require medication. Antihistamines and benzodiazepines frequently are prescribed as vestibular suppressants; however, the efficacy of these medications remains unclear. The authors of this study performed a systematic review and meta-analysis assessing the relative efficacy of benzodiazepines and antihistamines when compared to each other, other active treatments, placebo, or no intervention in the treatment of acute vertigo from any underlying cause.
The authors reviewed randomized or quasi-randomized trials that compared any antihistamine or benzodiazepine with a comparator, placebo, or no intervention in patients with acute vertigo (durations of two weeks or less) of any etiology. The predefined primary outcome was change in 10- or 100-point vertigo or dizziness visual analogue scale (VAS) score at two hours after treatment. Secondary outcomes included change in nausea at two hours, the need for rescue medication or intervention at two hours, resolution of vertigo at one week, resolution at one month, improvement at one week, improvement at one month, and nystagmography results. A good or satisfactory improvement was defined as patient-rated improvement with at least a 50% reduction in symptom severity on any numeric scale.
There were 17 studies with a total of 1,586 participants included in the quantitative results; most patients were diagnosed with “generalized or nonspecific peripheral vertigo.” The following antihistamines were used: betahistine (two studies), cinnarizine (four studies), dimenhydrinate (seven studies), flunarizine (two studies), meclizine (one study), and promethazine (two studies). Antihistamines were compared to benzodiazepines (three studies), placebo or no treatment (seven studies), and other active controls (six studies). The only benzodiazepines studied were lorazepam and diazepam, which were compared with antihistamines (three studies) or placebo (one study). Four studies enrolled patients with BPPV and compared Epley repositioning maneuvers alone to Epley maneuvers in combination with antihistamines.
For the primary outcomes, seven studies totaling 802 patients were included in the meta-analysis. All studies compared antihistamines to other treatments. Antihistamines were associated with a 16.1-point greater decrease in vertigo (95% confidence interval, 7.2 to 25.0) than benzodiazepines based on a VAS at two hours after administration of medication. There were no differences seen in the secondary outcome measurements. There was no statistically significant difference in improvement on the vertigo VAS at one week following treatment, no increase in the likelihood of complete resolution of symptoms at one week, and no differences in improvement or complete resolution of symptoms at one month. Of the six trials that included nystagmometry measurements, one suggested that dimenhydrinate was superior to diazepam and four showed greater improvement in nystagmus in patients treated with antihistamines compared with placebo. The authors concluded that there is moderately strong evidence that single-dose antihistamines result in greater improvement in vertigo at two hours than single-dose benzodiazepines.
COMMENTARY
The treatment of vertigo remains challenging. Vertigo has many etiologies; the benefit of any specific treatment may vary depending on the specific diagnosis. Patients often have difficulty describing their symptoms, physicians do not always agree on terminology, and there are no diagnostic studies that provide definitive diagnoses. Although this meta-analysis provides support for the use of antihistamines over benzodiazepines for the management of acute vertigo, it does not provide recommendations based on the etiology of the complaint or for patients with chronic vertigo.
Going forward, additional randomized controlled studies comparing treatments of vertigo are needed. It would be best if there were well-defined diagnostic criteria so that different causes of vertigo can be assessed independently.