Studies have evaluated the adverse impacts of non-adherence to medication among adults with type 2 diabetes, including poor outcomes and increased healthcare costs. However, data are limited on adolescent patients. The Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) study examined whether additional oral medications or insulin impacted adherence to primary study medication. The TODAY study included 699 patients aged 10 to 17 years who were recently diagnosed with type 2 diabetes. Patients were classified as adherent (≥80% taken by pill count) or non-adherent (<80%); adherence rates were compared by patients who did and did not have additional medications. At 36 months, just less than half of patients (46.3%) were taking additional oral medications, and 31.9% were on insulin. Study medication adherence did not differ with additional oral medications: zero additional medications prescribed, 55.1%; one, 67.1%; and two or more, 56.7% (P=0.16). Female patients taking oral contraceptives had higher 36-month adherence (65.2% vs. 55.8%; P=0.0054), and patients on insulin had lower 36-month adherence (39.7% vs. 59.3%; P<0.0001). Patients with depression at baseline had lower adherence (P=0.008). The researchers called for future studies to explore potentially modifiable risk factors associated with medication adherence.