The following article concludes: "Topical non-steroidal anti-inflammatory drugs are effective in relieving pain in acute and chronic conditions."

BMJ. 1998 Jan 31;316(7128):333-8
Quantitative systematic review of topically applied non-steroidal anti-inflammatory drugs.

Moore RA, Tramer MR, Carroll D, Wiffen PJ, McQuay HJ.
University of Oxford, Oxford Radcliffe Hospital, Headington.

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Free full text article available at bmj.com: http://bmj.bmjjournals.com/cgi/content/full/316/7128/333

The following article reports "The systemic concentrations of ketoprofen have also been found to be 100 fold lower compared to tissue concentrations below the application site in patients undergoing knee joint surgery. Topically applied ketoprofen thus provides high local concentration below the site of application but lower systemic exposure."

Pharm Res. 1996 Jan;13(1):168-72
Percutaneous absorption of ketoprofen from different anatomical sites in man.

Shah AK, Wei G, Lanman RC, Bhargava VO, Weir SJ.
Pfizer Inc., Central Research Division, Groton, Connecticut 06340, USA.

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