Summary: Aceclofenac is exceptional among non-steroid anti-inflammatory drugs because of the inhibition of COX-2, cytokines, interleukines and tumor necrosis factors; a positive influence on neutrophil adhesion molecules and glycosaminoglycans synthesis; chondroprotective metabolite 4-hydroxyaceclofenac; and limiting levels of proinflammatory nitric oxide. It results in high efficacy in limiting pain and inflammation; a long analgesic effect; low frequency and limited intensity of gastrointestinal side-effects; and positive influence on joint cartilage. In case of acute pain, or chronic pain exacerbation, requiring only short therapy (up to 7 days) – in patients with a previous negative history of gastrointestinal illness that may increase the risk of side-effects – aceclofenac administration without any accompanying gastro-protective drugs can be considered, which reduces the cost of therapy, limits polytherapy and increases compliance. Aceclofenac is a dependable painkiller in cases of chronic pain syndromes, especially resulting from degenerative diseases of motor system organs, as dosage does not require adjustments in elderly patients.