Which NSAID poses a high risk of causing edema?

Diclofenac is known to pose a higher risk of causing edema among the NSAIDs mentioned. This risk is related to its effect on the renal system and fluid retention. When NSAIDs inhibit the enzyme cyclooxygenase (COX), they can lead to a reduction in prostaglandins, which play a significant role in maintaining renal blood flow and function. Reduced prostaglandin synthesis can result in sodium retention, increased blood volume, and ultimately edema.

Diclofenac has a higher affinity for COX-2 than for COX-1, which can lead to more pronounced effects on renal function and associated fluid retention compared to other NSAIDs. Medications like indomethacin, naproxen, and ketorolac also have the potential to cause edema, but clinical evidence suggests that diclofenac is more consistently associated with this side effect in the context of long-term use and higher doses. Using diclofenac in patients with pre-existing conditions that predispose them to fluid retention, such as heart failure or kidney disease, necessitates careful monitoring due to this heightened risk.