Effect of roxithromycin on respiratory bacterial infection in mice.

The effects of roxithromycin (RXM), an antibiotic of the macrolide family, on respiratory bacterial infection in mice were examined. BALB/c mice were administered with RXM orally at a dose of 5.0 or 2.5 mg/kg once per day for 14 days. On day 2 after the final drug administration, the mice were nasally infected with Haemophilus influenzae. RXM dose dependently inhibited the pathological changes in lung tissues induced by H. influenzae infection. RXM also enhanced 2',5'-oligoadenilate synthetase production in response to infection.