Small bowel permeability--a variable effect of NSAIDS

The baseline permeability of small bowel in 57 healthy volunteers was assessed by measuring the mannitol and chromium-EDTA recovery in a 5-hour urine collection after ingestion of a drink containing a mixture of 1 g of mannitol and 3.7 MBq of 51Cr-EDTA. Subjects were treated with medication for 1 week followed by permeability studies as described above. The regimens used were diclofenac sodium (Voltaren) 50 mg po tid (21 subjects), Voltaren SR 75 mg bid for 1 week (34 subjects), indomethacin 50 mg tid (10 subjects), and tenoxicam (Mobiflex) 20 mg daily (13 subjects). There was no significant difference between the mannitol recoveries at baseline or after any of the drugs. The permeability was clearly increased by indomethacin and by Voltaren SR. Conventional-release Voltaren increased permeability, but the results were not significantly above baseline. Mobiflex had no influence on the measured permeability. Our results suggest that the SR preparation of diclofenac has a more pronounced effect than regular diclofenac sodium; thus different NSAIDs and different preparations of the same NSAID may have different effects on small bowel permeability.