Effect of carprofen and indomethacin on gastric function and the content of prostaglandins E2 and F2 alpha in human gastric juice.

The effect of indomethacin (2 X 50 mg daily) and carprofen (2 X 150 mg daily) on gastric secretion and the generation of prostaglandins PGE2 and PGF2 alpha in gastric juice, was investigated in a single blind cross-over study in eight healthy volunteers lasting one week. We observed no statistically significant change in basal and pentagastrin-stimulated gastric secretory parameters (outputs of gastric acid, N-acetyl-neuraminic acid and pepsin) before and after treatment with indomethacin and carprofen. However, an inhibitory effect was found on the output of PGE2 and PGF2 alpha after pentagastrin stimulation. While both drugs diminished the output of PGF2 alpha to a similar extent, carprofen exerted a markedly weaker inhibitory effect on the output of PGE2 than did indomethacin. It is suggested that the gastric tolerability of non-steroidal anti-inflammatory drugs (NSAIDs) is related to their inhibitory potency on PGE2 formation, in the sense that weak inhibitors of PGE2 cause less damage to the gastric mucosa than do strong inhibitors.