Access to Psychiatric Medications in Unhoused Populations: Implications for Hospitalization and Readmission Rates

Persons experiencing homelessness (PEH) face disproportionately high rates of psychiatric illness and hospitalization, with mental illness prevalence reported as high as 76.2%—significantly higher than in the general population. Psychiatric treatment for PEH is often hindered by systemic barriers to care, including medication nonadherence stemming from fragmented healthcare delivery, stigma, transportation challenges, and unstable housing. This discontinuity contributes to elevated readmission rates, with studies showing 30-day psychiatric readmission rates up to 2.04 times higher for unhoused individuals. Medication access is further complicated by inappropriate prescribing patterns and difficulty in maintaining treatment regimens for chronic mental illnesses such as schizophrenia and bipolar disorder. Multifactorial barriers—spanning patient-level, treatment-related, and structural factors—worsen adherence. Evidence-based interventions such as Assertive Community Treatment, Customized Adherence Enhancement with long-acting injectables, and Housing First models have shown success in improving treatment continuity and reducing psychiatric symptomatology. Emerging solutions like street medicine and mobile outreach deliver low-barrier care directly to shelters and encampments. Addressing psychiatric medication adherence among PEH is not only a clinical priority but a public health imperative, requiring integrated, compassionate, and housing-informed care models.