Paracetamol and simple analgesics are probably just as effective as non steroidal anti inflammatory drugs (NSAIDs) for relieving pain in osteoarthritis (OA).
Professor P A Dieppe and other researchers from the University of Bristol, reviewing clinical trials of paracetamol and NSAIDs for OA to date concluded that paracetamol reduced pain and tenderness significantly. None of the literature supports the widespread assertion that NSAIDs are better at reducing pain and joint stiffness than paracetamol alone.
The Bristol researchers furthermore said that the entire approach to osteoarthritis, which strikes one in eight people over 65, has been "misdirected" by concentrating on the role of NSAIDs. These drugs primarily reduce inflammation as well as pain, whereas OA causes only minor inflammation, which doesn't really account for most of the pain of the disease.
"The models adopted to develop NSAIDs are irrelevant to osteoarthritis, but patients with this disorder are now the main recipients of these drugs," they said. In one study, more than three quarters of frequently prescribed NSAIDs were given for OA.
They also dispute the conclusions of the hundreds of papers on NSAIDs now published. Most of the studies showing pain relief from NSAIDs were conducted over a few weeks, whereas the pain of osteoarthritis can be present for months or years in most cases. Furthermore, the studies tend to compare different NSAID agents against each other, showing little difference. The researchers were mystified to discover that there are virtually no studies comparing the NSAIDs with the simple analgesics.
"Given the huge number of studies of NSAIDs in osteoarthritis, it is tempting to conclude that one of the main reasons for this paucity of comparative studies. . . must be the vested interests of the pharmaceutical industry," they said.
Professor Dieppe and his cohorts said that simple painkillers have many advantages over NSAIDs. Besides being cheaper, they do not have the toxic effects of NSAIDs, particularly gastrointestinal damage, which is highest in elderly women, the very group in which OA is most prevalent. "Many patients with osteoarthritis could be managed as well or better with simple analgesics and rubefacients [which cause warming of the skin] than with NSAIDs, they said.