Antihistamines superior to benzodiazepines in the treatment of acute vertigo: JAMA

USA: Acute vertigo is a distressing and disabling condition. Antihistamines and benzodiazepines are frequently prescribed as "vestibular suppressants," but their efficacy is unclear.

A new study published in the Journal of American Medical Association - Neurology suggests that antihistamines are superior to benzodiazepines in reducing vertigo.

Disabling vertigo can occur suddenly. Although their effectiveness is unknown, antihistamines and benzodiazepines are commonly administered as "vestibular suppressants." In order to evaluate the effectiveness of antihistamines and benzodiazepines in the management of acute vertigo for any underlying reason, Benton R. Hunter and colleagues carried out this study.

Without regard to language constraints, the databases of ClinicalTrials.gov, EMBASE, CENTRAL, CINAHL, Scopus, and PubMed from inception to January 14, 2019, were searched. The included studies' bibliographies and pertinent reviews were also checked. For patients with acute vertigo lasting two weeks or less, randomized clinical trials (RCTs) contrasting the use of an antihistamine or benzodiazepine with another comparator, a placebo, or no intervention were also included. Research using healthy volunteers, preventive therapy, artificial vertigo, and studies contrasting two drugs from the same class were all disregarded.

Data were extracted, and each study's risk of bias was evaluated independently by two authors in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) criteria. Changes in 10- or 100-point Visual Analog Scale (VAS) ratings for vertigo or dizziness at 2 hours following treatment were the designated main outcome. The usage of rescue medicine at two hours, a change in nausea VAS ratings at two hours, and an improvement or disappearance of vertigo at one week or one month were all considered secondary outcomes.

The key findings of this study were as follows:

1. 17 of the 27 studies found in the systematic review that totaled 1586 individuals were included in the quantitative meta-analysis.

2. Single-dose antihistamines significantly improved 100-point VAS ratings more than benzodiazepines did, but not more than other active comparators, according to seven trials that involved a total of 802 people.

3. Daily benzodiazepines or antihistamines were not shown to be more effective than a placebo for 1 week or 1 month. RCTs examining outcomes at 1-week and 1-month intervals often had a high risk of bias, whereas those comparing the immediate effects of drugs (within 2 hours after a single dosage) generally had a low risk of bias.

In conclusion, the data that was provided did not demonstrate a link between using benzodiazepines and better results for any type of acute vertigo.The findings of this study suggest that antihistamines may be superior to benzodiazepines in the treatment of acute vertigo and that the use of the latter should be discouraged.

Other data however revealed that people with acute vertigo may not benefit from taking antihistamines every day. Larger randomized studies contrasting benzodiazepines and antihistamines with placebo may be able to more clearly determine the relative effectiveness of these drugs.

Reference:

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. Published online July 18, 2022. doi:10.1001/jamaneurol.2022.1858