Background: Antiretroviral therapy (ART) has reduced the rates and changed the causes of hospital admission. However, human immunodeficiency virus-positive intravenous drug users (HIV-IDU) continue to have increased hospitalizations and discharge diagnosis are less defined in the late ART era. Our aim was to examine ART use, HIV-1 RNA suppression, and hospital discharge diagnoses among HIV-IDU admitted to an urban hospital.Methods: A retrospective analysis was made of HIV-IDU admitted for medical causes for the first time (2006-2010). Surgical, obstetric, or mental (except HIV-associated neurocognitive disorder) diagnoses were excluded. Clinical characteristics, number of admissions, and primary discharge diagnoses were determined for each patient.Results: Three hundred and seventy-five admissions were recorded among 197 hospitalized HIV-IDU. Lifetime prevalence of ART use was 83.2% (164 of 197) and the rate of HIV-1 RNA <50 copies/mL was 38.1% (75 of 197). Primary discharge diagnosis groups were as follows:acterial infections (59.2%), chronic end-organ damage (16.8%), complications derived from injected drug use (16.8%), malignancies (9.1%), and opportunistic infections (6.6%). Chronic end-organ damage was diagnosed more frequently in patients with HIV-1 RNA <50 copies/mL (36% vs 4.9%; P < .000), and complications derived from injected drug use (23.8% vs 5.3%; P < .0008) and acquired immune deficiency syndrome (AIDS) opportunistic infections (19.8% vs 1.3% P < .019) were usually diagnosed in patients with HIV-1 RNA detectable viral load. Conclusions: Human immunodeficiency virus-positive intravenous drug users are admitted to hospitals mainly for non-AIDS-related illnesses; however, sustained HIV-1 RNA viral load suppression is poor and determines hospital discharge diagnoses. Providers need to be aware of the management of HIV-related comorbidities and reinforce strategies to improve ART retention in this population.