Diclofenac belongs to a group of medicines called nonsteroidal anti-inflammatory drugs (NSAIDs) that work by:
Inhibiting the action of cyclooxygenase enzymes COX-1 and COX-2, thus inhibiting the formation of prostaglandins.
It may also inhibit the aggregation/activation of neutrophil cells, inhibit the movement of proinflammatory cells, reduce the level of proinflammatory cytokines, and alter the activity of lymphocytes.