The effect of tiaprofenic acid and indomethacin on in vitro prostaglandin synthesis by rat, rabbit and human stomach tissue.

We compared the inhibitory effect of two non-steroidal anti-inflammatory drugs (NSAIDs), tiaprofenic acid and indomethacin, on in vitro prostaglandin (PG) synthesis by human, rat and rabbit stomach/duodenal tissue. Both drugs were equipotent inhibitors of PGE2, 6-oxo-PGF1 alpha (the stable metabolite of prostacyclin, PGI2) and PGF2 alpha. These findings suggest that tiaprofenic acid does not offer 'gastric protection' by sparing the cytoprotective PGs, as previously claimed. Our in vitro findings are in agreement with the results of clinical trials which show that faecal blood loss and epigastric discomfort are of a similar pattern whether tiaprofenic acid or other NSAIDs are administered.