TOPICALLY APPLIED NSAIDs IN THE TREATMENT OF PAIN

The mainstay of management of inflammation and pain associated with arthritis and soft tissue injuries has been oral nonsteroidal anti-inflammatory drugs (NSAIDs). Topically applied NSAID products are not readily available in N. America for two reasons: 1) extensive studies of efficacy and toxicity by the topical route are very limited, and 2) most NSAIDs have lost their patents which makes the development of topical preparations unprofitable for drug companies. Nevertheless, topical NSAIDs are widely available and are prescribed extensively in other countries. Topical NSAIDs have four major advantages: 1) higher concentrations of NSAIDs are delivered to the desired site (e.g. up to 100 times higher NSAID occurs in synovial fluid compared to that from NSAID blood levels; 2) only 1-3% of NSAID is systemically absorbed, reducing the possibility of gastrointestinal upset or ulcers; 3) low blood levels reduce the incidence of drug interactions; 4) incidence of low skin irritation at the application site.