The clinical efficacy of a macrolide antibiotic, roxithromycin, was evaluated in 24 patients affected by acute odontogenic infections. Patients were treated with a first dose of 300 mg p.o. which was followed by 150 mg p.o. 12-hourly for the following two days. Total responses were evaluated by an arbitrary scale. The results showed that an excellent and good response was obtained in 99.96% of treated patients. On the basis of clinically compared data and the drug safety it may be concluded that roxithromycin can be successfully used in the treatment of odontogenic infections.