Injection drug use (IDU) accounts for 12% of all illicit drug use in the United States. Intravenous routes are often preferred because of the rapid drug response. Intravenous injecting typically begins in the veins of the arms and upper body, but as these sites become more difficult to find, the veins of the groin, leg, and feet are used. Complications of IDU include venous scarring and collapse, abscess formation, nerve and muscle damage, and lymphatic blockage. In addition, IDU augments or intensifies the typical chronic venous disease (CVD) risk factors affecting the general population. In this review, Pieper et al point out the importance of obtaining a substance-abuse history when evaluating for risk of CVD.