To prepare a therapeutic agent for hepatopathy, capable of suppressing the production of cytokine and usable as a readily administrable oral agent without severe adverse side effects by making the agent include a specific compound as an active ingredient therein.

This suppressant for production of cytokine comprises ethyl 1,4-dihydro-5-isopropoxy-2-methyl-4-(2-trifluoromethylphenyl)-1-,6-naphthyridine-3- carboxylate therapeutic agent as an active ingredient. The daily dose thereof is usually about 0.5-100mg of the above compound as the active ingredient for an adult in the case of a parenteral injection and about 5 to 100mg for oral administration.