Gastric mucosal injury induced by application of indomethacin, as a
nonsteroidal anti - inflammatory drug (NSAID). is a well- documented phenomenon.
This study examined the effect of acetaminophen (paracetamol)
on indomethacin - induced gastric erosions. One hundred adult albino
rats of both sexes, weighing 200 - 250 gm were divided into two main
groups, including a group of 10 rats acts as a controL The first group was
to study the effect of a single oral dose of indomethacin. paracetamol and
both drugs. on the gastric mucosa. and the second group was to study
the effect of repeated administration of each drug and both drugs together.
The animals were killed and the histopathological changes of the
stomach were examined microscopically.
Single therapeutic dose of indomethacin was found to induce multiple
gastric erosions which these were more marked after repeated administration
of the drug. Single dose or prolonged administration of para.-etamot
were followed by very minimal changes in the gastric mucosa. Simultaneous
administration of both drugs was found to reduce the
pathological lesions induced by indomethacin alone, whereas the pretreatment
with paracetamol one hour before a single oral dose of indomethacin
did not affect its erosive activity. Post - treatment with paracetamol
reduces the erosive effect of indomethacin either in a single dose or
after repeated administration. The pathogenesis of gastric erosions and
ulcers was believed to be due to prostaglandin inhibition. Indomethacin
was known as a potent inhibitor of prostaglandin synthesis. whereas paracetamol is a very weak inhibitor of prostaglandin production.
It is also found that paracetamol had a protective action against the
erosive effect of indomethacin and this appears to be mediated by mucosal
regeneration, probably resulting from increased production of mucosal
growth factors.
So. the use of paractamat as antipyretic and analgesic drug is recommended
instead of indomethacirt, or they are administrated siniultaneously
with or after irtdomethacin when there is a possibility of gastric mucosa/
injury, especially in prolonged treatment. |
