Upper respiratory tract infections, particularly pharyngitis and acute otitis media (AOM) are the commonest diseases in children. Although viruses are the main causative agents, bacteria may play an important role. With regard to antibiotic therapy, clinicians must solve two problems: differentiation between viral and bacterial aetiology and choice of the optimal drug for each bacterial disease. In patients with pharyngitis the identification of group A haemolytic streptococci as the causative agent may be very difficult if only clinical and haematological data are considered. Throat culture is time consuming and difficult to perform in ambulatory practice; the recent techniques for rapid detection of streptococcal antigens are a possible answer to this problem. In bacterial pharyngitis a single injection of benzathine penicillin is considered to be first choice. However local pain and the significant increase of the relative risk of allergic problems in comparison with the decrease of incidence of rheumatic fever may shift therapeutic preference towards macrolides. The recently marketed ones, especially miocamycin, seem to offer easier administration, fewer side-effects and better efficacy. With regard to AOM, the differentiation between bacterial and viral disease is less important because over 70% of cases are of bacterial origin. Besides, an exact aetiological diagnosis is possible only by tympanocentesis, an invasive method. In Italy amoxicillin is still the drug of choice: a twice-daily regimen has been demonstrated to be as effective as the traditional thrice-daily schedule.