Abstract Background: In the United States, colorectal cancer (CRC) is a public health concern, as it is the second leading cause of cancer-related death, accounting for over 50,000 deaths annually. In addition to its high mortality, CRC is associated with significant comorbidities including pain and psychiatric symptoms, particularly in late-stage disease. Supportive care medications (SCM) are frequently used for symptom management and improving health-related Quality of Life (HRQoL). Racial disparities in clinical outcomes including HRQoL have been reported in CRC. While racial disparities have been described in the use of SCM for some cancer types, no investigation of SCM use in late-stage CRC have been performed. The purpose of our study was to explore the relationship between SCM use and race/ethnicity in patients with metastatic CRC. Methods: We used the National Cancer Institute Surveillance Epidemiology and End Results (NCI SEER)- Medicare-linked database to analyze all patients with a CRC diagnosis and a newly initiated outpatient prescription claim for an SCM of interest from 2009-2018. Patients on SCM before cancer diagnosis or who had non-metastatic CRC at diagnosis were excluded. We assessed six SCM classes: opioids, non-opioid analgesics, skeletal muscle relaxants, antidepressants, anxiolytics, and antipsychotics. Results: After application of inclusion/exclusion criteria, 28, 212 patients were included in the final analysis (White: 72.8%, Black: 12.7%, Hispanic: 9.5%, Asian: 4.6%, Native American: 0.4%). After controlling for socioeconomic factors and compared to non-Hispanic White patients, there were significant differences across multiple SCM drug classes. When considering pain medications, these differences were bi-directional. Black patients were less likely to receive opioids (adjusted Odds Ratio [aOR] 0.86, 95% CI: 0.80-0.93), while Hispanic patients were more likely to receive opioids (aOR: 1.12, 95% CI: 1.03-1.22) and non-opioid analgesics (aOR 1.22, 95% CI: 1.06-1.40). Asian patients were more likely to receive non-opioid analgesics (aOR 1.71, 95% CI: 1.45-2.03), but less likely to receive skeletal muscle relaxants (aOR 0.60, 95% CI: 0.43-0.82). When considering psychiatric medications, decreased use among all racial groups was noted for antidepressants (Black: aOR 0.53, 95% CI: 0.50-0.60; Hispanic: aOR 0.82, 95% CI: 0.75-0.90; Asian: aOR 0.48, 95% CI: 0.42-0.56), and anxiolytics (Black: aOR 0.43, 95% CI: 0.38-0.49; Hispanic: aOR 0.76, 95% CI: 0.67-0.85; Asian: aOR 0.45, 95% CI: 0.37-0.55). Among antipsychotics, only Asian patients had less use compared to non-Hispanic White patients. Conclusion: Racial disparities in the use of pain and psychiatric medications among patients with late-stage CRC were present, even after controlling for multiple confounders. Further investigation is needed to understand drivers and their impact on HRQoL outcomes. Citation Format: John M. Allen, Olga M. Trejos Kweyete, Yi Guo, Sherise C. Rogers, Lisa Scarton, David L. DeRemer, Chardae Whitner, Diana J. Wilkie. Racial disparities in pain and psychiatric medication use in patients with metastatic colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4834.