The objective of this study was to define the pattern and time course of use of ED treatments in a Veterans Affairs (VA) medical center and to identify clinical or demographic variables that are associated with the use of second- or third-line ED treatments. We identified 702 men treated for ED at the Greater Los Angeles Veterans Affairs between 2007 and 2013. We extracted demographics, Charlson co-morbidity score, pertinent surgical/medication history as well as use of ED treatments from medical records. On multivariate analysis, age over 65 (OR 1.83, 95% CI: 1.31-2.56) and Charlson co-morbidity score of 1 (OR 1.77, 95% CI: 1.13-2.77) and 2+ (OR 2.07, 95% CI: 1.28-3.36) were significantly associated with use of medicated urethral suppositories for erection (MUSE)/intracorporal injections (ICI) compared with PDE5i/erection devices. Across all men who used second- or third-line treatments, median time until receiving MUSE was 0.6 years and median time until receiving ICI/implant was 2 years. We conclude that men who will ultimately use more invasive ED treatments, such as men with more co-morbidities, tend to have a prolonged treatment course. This information may be incorporated into a shared decision-making model for more efficient treatment of ED.