Gastroduodenal lesions associated with two different piroxicam formulations. An endoscopic comparison.

This endoscopic study was performed to compare the gastroduodenal endoscopic findings after short-term treatment with plain and enteric-coated piroxicam tablets. Sixteen healthy male volunteers (mean age, 22 years; range, 19-27 years) were included in a double-blind, randomized study in which 20 mg piroxicam was given once daily for 2 weeks as plain tablets or enteric-coated tablets in a crossover fashion. The washout period was 5 weeks, and endoscopy was performed before each treatment period to ensure base-line conditions. Endoscopic evaluation of the stomach and duodenum was performed, with separate registration of the duodenum distally to the duodenal bulb. Visual analogue scales of 150 mm were used for grading the mucosal lesions, with separate registration of mucosal injection and erosive and haemorrhagic lesions. A 5-point scale (Lanza scale) was also used, to compare the two scoring systems. A significantly lower lesion score was found with the enteric-coated formulation for all endoscopic variables in both scoring regions. The sum of visual analogue scale scores in the stomach/duodenal bulb after treatment was 121 mm and 74 mm, respectively (p < 0.01), and in the middle and distal duodenum the corresponding figures were 54 mm and 23 mm (p < 0.01). The fixed-point scoring gave identical conclusions, as did the separate scoring by a different investigator evaluating the same endoscopies. Subjective symptoms were similar for the two formulations, and no carryover effects were detected. We conclude that enteric coating of piroxicam tablets may offer a means of protecting the gastroduodenal mucosa in short-term treatment of healthy subjects.

Comparison of the gastrointestinal side effects of naproxen formulated as plain tablets, enteric-coated tablets, or enteric-coated granules in capsules.

We studied the gastrointestinal side effects of three formulations of naproxen in 18 healthy male volunteers. In a Latin-square design crossover study, the subjects received 500 mg naproxen twice daily for 7 days as plain tablets, enteric-coated tablets, or enteric-coated granules in capsules. The 51Cr-EDTA absorption test was performed before and at the end of each drug period, to evaluate changes in the distal gut. The test dose was instilled distally in the duodenum to prevent lesions in the stomach from interfering with the evaluation. Upper endoscopy was performed at the same intervals, scoring changes in the middle and distal duodenum separately from findings in the stomach and duodenal bulb. The nature and severity of adverse effects were recorded for each treatment period. Non-parametric methods were used for statistical evaluation. All drugs induced a significant increase in 51Cr-EDTA absorption, but we did not detect any difference between the three formulations. All formulations were associated with a significant increase in all the endoscopic findings monitored. Enteric-coated tablets induced significantly less lesions than enteric-coated granules in the stomach and duodenal bulb, and an advantage over plain tablets was indicated. No difference was seen in the middle and distal duodenum. The proximal endoscopic scores were not correlated to those found in the middle and distal duodenum. Evaluation of the small and large bowel should probably be included in clinical studies of NSAIDs, but our findings suggest that the importance of transfer of mucosal lesions to the distal gut by enteric coating may have been overemphasized.

Gastroscopic findings after treatment with enteric-coated and plain naproxen tablets in healthy subjects.

The damaging effect of enteric-coated and plain naproxen tablets on the gastric mucosa was studied in 12 healthy subjects before and after 7 days' treatment in a randomized, double-blind, double-dummy, cross-over trial. Both formulations of the drug caused mucosal lesions, but the extent of the damage was significantly decreased after enteric-coated naproxen as compared with plain tablets. The subjects' preference was significantly in favour of the enteric-coated naproxen tablets. The plasma naproxen concentration was significantly higher after treatment with enteric-coated naproxen than after treatment with plain tablets. In conclusion, the results of the study indicate that naproxen might damage the gastric mucosa by local and systemic effects and that the local effect might be prevented by enteric coating of the tablets.