Allogeneic hematopoietic cell transplant (HCT) is a curative therapy for malignant and non-malignant blood diseases. Drug use may be associated with adverse outcomes. We performed a retrospective analysis to assess non-relapse mortality (NRM) and overall survival (OS) in HCT patients with drug use. The medical charts of 232 patients were reviewed. Recipients of matched unrelated donor (MUD) or matched related donor (MRD) transplants were included. Drug use was defined by either metabolic evidence or provider documentation prior to transplant. Transplants were MUD (n = 148) or MRD (n = 84). Median follow-up duration was 15.5 months. There were 35 (15%) patients in the drug use group and 197 (85%) patients in the control group; 49% and 60.4% were in remission at the time of transplant, respectively. In univariate analysis, drug use was associated with a 3-year cumulative incidence of NRM of 43% vs 29% for the control group (p = 0.048), and an HR of 1.75, (95% CI: 1.02-2.99). After controlling for age, sex, disease status, and graft type, drug use was associated with a hazard ratio (HR) of 1.6 (95% CI: 0.95-2.92) for NRM, and an HR 1.2 (95% CI: 0.74-1.94) for OS. Larger cohorts may be needed to further evaluate this association.