Class of 2017 Abstract / Objectives: To assess the incidence of medication-induced corrected QT (QTc) interval in patients taking two or more QTc prolonging medications and to identify which risk factors are associated with QTc prolongation. Methods: This retrospective chart review examined QTc prolongation in adult patients admitted to Banner University Medical Center South Campus (BUMC South) received at least two QTc prolonging medications. Patients were assessed for risk factors of QTc prolongation, number of QTc prolonging drugs received, and presence of QTc prolongation. Results: Of the patients who received two, three, or four or more QTc prolonging drugs, 43.4%, 67.3%, and 45.5%, experienced QTc prolongation, respectively (p < 0.05). Those who received three QTc prolonging drugs had a greater incidence of QTc prolongation compared to those who received two (p = 0.0089) or four or more (p = 0.049) QTc prolonging drugs. There was no difference in incidence of QTc prolongation in those receiving two versus four drugs (p = 0.084). The incidence of QTc prolongation was associated with risk factors including a history of cardiovascular diseases, electrolyte disturbances, and being female (p < 0.05). Conclusions: An increase in the number of QTc prolonging drugs received was not associated with a corresponding increase in the incidence of QTc prolongation. Being female, having electrolyte disturbances, or a history of cardiovascular disease may increase the risk of QTc prolongation.