Epidemiological studies of patients taking prescribed non-steroidal anti-inflammatory drugs (NSAIDs) show that these drugs are associated with a three to 10-fold increased risk of bleeding, perforation, hospitalisation and death.1 Primary studies and meta-analyses also show that NSAIDs differ in their risk. Ibuprofen is consistently associated with lower risks than the group as a whole whereas other NSAIDs such as piroxicam and azapropazone seem to be associated with relatively high risks.

In recent years a number of NSAIDs have become available over the counter. This may partly reflect patent expiry, anticipation of a new generation of NSAIDs (COX-2 selective or NO-NSAIDs) and recognition that the absolute risks of short term, low dose treatment are relatively low.

The problem has been to assess the safety of drugs in this setting. In their study Strom et al have attempted to quantify the risks of over the counter naproxen sodium by reference to a prescribing situation that tried to replicate intended patterns of over the counter use. Information was gathered from the Computerized On-Line Medical Pharmaceutical Analysis and Surveillance System (COMPASS) database for Michigan and Ohio, USA. Patients were eligible for study if they …