A gastroscopic and histological double-blind study of the effects of diclofenac sodium and naproxen on the human gastric mucosa.

The effects of diclofenac sodium and naproxen on the gastric mucosa were studied in a double-blind trial by gastroscopy, gastrophotography and histological examination of the mucosa in six healthy volunteers. Detectable lesions were evident in the mucosa of four subjects after administration of both drugs, and the lesions were more extensive after the ingestion of naproxen than after diclofenac sodium in all of these cases. The most serious lesions verified by both gastroscopy and histology always occurred after exposure to naproxen. The histology of the gastric mucosa of two subjects with severe lesions showed spotty to moderate chronic superficial gastritis, whereas the overall histological appearance of the mucosa was normal in subjects with slight or moderate lesions after drug administration. The maximal acid output was positively correlated with the severity of the lesions. Subjective symptoms occurred in one person during diclofenac sodium and in three during naproxen administration.