(4-Propyl-2,3-dichlorohenoxy)acetic Acid-D3 is a deuterium labelled analogue of (4-Propyl-2,3-dichlorohenoxy)acetic Acid (P835208), an impurity of Ethacrynic Acid (E676000) that is a diuretic used to treat high blood pressure and swelling caused by congestive heart failure, liver failure, and kidney failure.