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Benzodiazepines or Antihistamines for Acute Vertigo?

— Evidence does not support benzodiazepines for any outcomes, meta-analysis shows

MedpageToday
A blurred photo of a man with his eyes closed and hand on his head experiencing vertigo

Moderately strong evidence suggested antihistamines provide greater acute vertigo relief than benzodiazepines, a meta-analysis showed.

Single-dose antihistamines led to a 16.1-point (95% CI 7.2-25.0) greater decrease in vertigo symptom scores on a 100-point visual analog scale (VAS) compared with single-dose benzodiazepines at about 2 hours after treatment, reported Benton Hunter, MD, of Indiana University School of Medicine in Indianapolis, and colleagues in .

Antihistamines were similarly effective as other active comparators, with a mean difference of 2.7 points (95% CI -6.1 to 11.5), the researchers said.

"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," Hunter and colleagues wrote.

"Furthermore, the available evidence did not support an association of benzodiazepine use with improvement in any outcomes for acute vertigo," they stated.

Vertigo affects up to 20% of adults and is more common in women and older adults. Repositioning techniques are the preferred treatment for benign positional paroxysmal vertigo (BPPV), but antihistamines and benzodiazepines also are frequently prescribed as vestibular suppressants, Hunter and colleagues noted.

"Symptom control for acute vertigo with vestibular suppressants may be indicated with or without a definitive diagnosis, and the efficacy of these medications remains unclear," they observed.

Correct treatment of acute vertigo depends on a correct diagnosis -- "something that cannot necessarily be taken for granted," wrote David Newman-Toker, MD, PhD, of Johns Hopkins Hospital in Baltimore, and colleagues, in an .

Adopting a symptomatic medication management approach to vertigo is not a risk-free proposition, the editorialists pointed out. BPPV not treated within 24 hours has more than double the risk of recurrence and is associated with 6.5-fold greater odds of falls, they noted. If antihistamines are used longer term, patients are exposed to risks from adverse effects and complications.

"Primary care physicians often treat vertigo with antihistamines for long periods of time (sometimes years or even decades)," Newman-Toker and colleagues wrote. "Therefore, patients may get 'stuck' taking vestibular suppressants after emergency department discharge and be given instructions to follow up in primary care."

Although neurology and otolaryngology societies have published , there is no guidance for an overall approach for patients with acute dizziness. In 2021, the Society for Academic Emergency Medicine began working on an overarching clinical guideline to help diagnose and treat people with acute dizziness and vertigo.

"This guideline, anticipated by late 2022, will make specific recommendations for diagnosis and initial management of patients with both episodic and acute vestibular syndromes," Newman-Toker 's group wrote.

Of 27 trials identified by Hunter and colleagues in their systematic review, 17 contributed to the meta-analysis, which included 1,586 participants. Seven trials totaling 802 participants evaluated the study's primary outcome of vertigo VAS scores at about 2 hours after treatment.

Most studies enrolled patients with generalized or nonspecific peripheral vertigo. Benzodiazepines were limited to lorazepam and diazepam, which were compared with placebo in one trial and with antihistamines in three trials.

Antihistamines included were betahistine, cinnarizine, dimenhydrinate, flunarizine, meclizine, and promethazine. "Although meclizine is a popular treatment for vertigo in the U.S., we did not find direct or indirect evidence that its efficacy differs from that of other antihistamines," Hunter and colleagues noted.

At 1 week and at 1 month, neither daily benzodiazepines nor antihistamines were superior to placebo. Trials comparing immediate effects of treatment after a single drug dose had a low risk of bias, but those evaluating 1-week and 1-month outcomes had a high risk of bias, the researchers said.

The analysis had several limitations, Hunter's group acknowledged. The outcome should be considered in the context of the small number of trials in the study. There's also no established clinically relevant difference for vertigo VAS scores, the researchers noted.

"We found a difference of 16 between antihistamines and benzodiazepines; this may be a patient-important difference, but its clinical relevance on a vertigo VAS is unclear," they wrote.

  • Judy George covers neurology and neuroscience news for ľֱ, writing about brain aging, Alzheimer’s, dementia, MS, rare diseases, epilepsy, autism, headache, stroke, Parkinson’s, ALS, concussion, CTE, sleep, pain, and more.

Disclosures

Benton and co-authors disclosed no relationships with industry.

Newman-Toker disclosed relationships with Natus Inc/Otometrics and with Interacoustics A/S; having a patent pending; and conducting research related to dizziness diagnoses including the NIH-sponsored AVERT clinical trial. He and a co-author also reported work as medicolegal consultants.

Primary Source

JAMA Neurology

Hunter BR, et al "Efficacy of benzodiazepines or antihistamines for patients with acute vertigo: a systematic review and meta-analysis" JAMA Neurol 2022; DOI: 10.1001/jamaneurol.2022.1858.

Secondary Source

JAMA Neurology

Edlow JA, et al "Correct diagnosis for the proper treatment of acute vertigo -- putting the diagnostic horse before the therapeutic cart" JAMA Neurol 2022; DOI: 10.1001/jamaneurol.2022.1493.