Increased Use and State-Level Variation of Esketamine Prescriptions Among Medicare Patients

Esketamine use for depression among Medicare patients was hypothesized to mirror the use observed in the Medicaid population. The author compared national population–corrected prescriptions and spending in the United States for 2019 and 2020. States outside a 95% confidence interval in the number of population-corrected prescriptions were identified. Prescriptions increased from 13.0 per 100,000 to 41.6 per 100,000 enrollees in 2019–2020, with an average 55-fold between-state variation. In 2019, providers in 10 municipalities did not prescribe esketamine, and providers in seven municipalities did not prescribe it in 2020. As hypothesized, esketamine use was low and highly variable, likely reflecting barriers to implementation and regional disparities.