Medications commonly contribute to erectile dysfunction (ED). By far the most common are various blood pressure medications, including clonidine (brand name Catapres) and the many beta-blocker drugs, among others. Diuretics, which are often used in the treatment of hypertension, may also worsen ED. You might be reading this and saying, "Great! High blood pressure causes ED and the medicines used to treat high blood pressure cause ED. What am I supposed to do?" You can't let high blood pressure go untreated, because it will worsen your vascular disease overall, and increase your risk of heart attack and stroke. The goal is to find the medicines that are the least likely to worsen ED. Fortunately, ACEs and ARBs have a fairly low risk of causing ED.