Naproxen Sodium and Weight Gain
Extensive clinical trials do not show a link between weight gain and naproxen sodium use. However, since the medicine may cause congestive heart failure, and rapid weight gain is the main symptom, notify your healthcare provider immediately if you develop rapid, unexplained weight gain or swelling. If you are taking naproxen sodium and notice a gradual increase in weight, try exercising more or eating a heart-healthy diet.
Side effects are possible with naproxen sodium (brand names include Aleve®, Anaprox®, and Naprelan®). Gradual weight gain, however, does not appear to be one of them. This data comes from clinical trials where naproxen sodium was extensively studied and side effects were documented.
Before medicines are approved, they must go through several clinical studies, where thousands of people are given a particular medicine and compared to a group of people who are given a placebo (sugar pill). In these studies, side effects are always documented. This way, it is possible to see what side effects occur, how often they occur, and how they compare to the group not taking the medicine. Side effects are then usually separated into those that occurred in more than 1 percent of people (common side effects) and those that occurred in less than 1 percent of people (rare side effects).
For people taking naproxen sodium, gradual weight gain was not reported as either a common or rare side effect. Weight gain has, however, been reported as a rare side effect with other nonsteroidal anti-inflammatory drugs (NSAIDs). But since it occurs in less than 1 percent of people taking NSAIDs, it is not possible to tell whether the weight gain is actually caused by the medicine itself, by other factors, or a combination of both.