Meclizine Use and Subsequent Falls Among Patients With Dizziness.

Importance: Among adults who present with dizziness, there is a critical need to identify and deimplement low-value and guideline-discordant care to mitigate the risk of falls over time. Meclizine, an antihistamine with anticholinergic properties, is the most used antiemetic vestibular suppressant in the US. Objective: To determine the factors associated with meclizine use and subsequent falls among patients aged 18 to 64 years and those aged 65 years or older with dizziness. Design, Setting, and Population: This cohort study assessed US commercial and Medicare Advantage claims among 805 454 adults (aged ≥18 years) with new diagnoses of dizziness between 2006 and 2015. Data were analyzed from July 2024 to February 2025. Exposure: Prescription of meclizine within 30 days of a new dizziness diagnosis. Main Outcomes and Measures: The main outcome measure was falls resulting in medical evaluation. Fall outcomes were attributed to meclizine use if they occurred within 60 days of a meclizine prescription. Associations of falls and meclizine with presentation setting, diagnoses, and sociodemographic characteristics were estimated with multivariable analyses. Results: Of 805 454 individuals with dizziness (502 055 women [62%]; median age, 52 years [range, 18-87 years]), 8% received a meclizine prescription. Among those prescribed meclizine, 5792 (9% overall; 10% [2189/21 700] aged 18-64 years and 9% [3603/40 138] aged ≥65 years) experienced an injurious fall. When adjusting for sociodemographics and clinical factors, a filled meclizine prescription was associated with subsequent falls in those aged 18 to 64 years (hazard ratio, 2.94; 95% CI, 2.81-3.08) and those aged 65 years or older (hazard ratio, 2.54; 95% CI, 2.42-2.66). Conclusions and Relevance: This study found that although meclizine may offer immediate vertigo relief, use is incongruent with guideline-concordant care for common vestibular diagnoses. Receipt of a meclizine prescription was associated with an increased risk of injurious falls among both patients aged 65 years or older and those aged 18 to 64 years with dizziness, who are already fall prone. Future prospective and mechanistic studies may further elucidate the relationship between vestibular suppressants and fall risk, and future guidelines that engage clinicians and patients to deimplement routine vestibular suppressant use for dizziness may be warranted.