It is common for patients seen by primary care physicians to be taking both nonsteroidal anti-inflammatory drugs (NSAIDs) and antihypertensive agents. If blood pressure control diminishes in these patients, the physician must evaluate the potential interaction between the two classes of medication. Although the increase in blood pressure secondary to NSAID use may be only 5 to 10 mm Hg, this increase may be enough to justify a change in medication. For this reason, it is important to evaluate the interaction between the two types of drugs and determine its clinical significance in specific patients.