PURPOSE: The purpose of this study was to determine the safety and effectiveness of implementing standing orders for nurse case managers to adjust antihyperglycemic medications. METHODS: A retrospective cohort design was used to assess outcomes in American Indian and Alaska Native people who received case management and medication adjustment and those who received only standard primary care. Patients with diabetes and evidence of keeping regular follow-up appointments for diabetes care (N = 2345) who all had baseline A1C >or= 7.0% were divided into 3 mutually exclusive groups for analysis: (1) those seen only by primary care providers (PCP; n = 1574); (2) those seen by nurse case managers (NCM; in addition to primary care) for diabetes education services only (n = 711); and (3) those who, in addition to a PCP and NCM visit, had medications adjusted by the nurse case managers (MA; n = 60). Outcome variables were number of visits with documentation of hypoglycemia (safety) and rate of A1C change (effectiveness). RESULTS: Documented hypoglycemia occurred more frequently with more intensive treatment. The MA group experienced the greatest rate of hypoglycemic events. The difference in hypoglycemia incidence between the groups was significant, but the number of events was small. Glycemic control improved most rapidly in the MA group, even after adjusting for potentially confounding variables. CONCLUSIONS: In this setting, hypoglycemia occurs infrequently in all groups, but at higher rates with more intensive treatment. Nurse case management, whether with or without medication adjustment, is effective in improving short-term glucose control.