BACKGROUND: The judicious prescription of antibiotics has become a central focus of professional and public health measures to combat the spread of resistant organisms. MATERIALS AND METHODS: A one-year multi-center prospective follow-up study of 1,320 healthy infants was conducted. The study aim was to determine the prevalence and identify the predictors of antibiotics misuse in viral respiratory illnesses among healthy infants in the first year of life. Infants born between August 2001 and February 2002 were recruited through the clinics and dispensaries of 117 pediatricians located in the Greater Beirut area of Lebanon. On each routine visit from birth until one year of life, pediatricians reported any episodes of upper respiratory tract infection (URTI; common cold) and bronchiolitis, as well as the treatment type, duration, and dose. Predictors that were considered included infant, maternal, and pediatrician characteristics. RESULTS: Of the 1,320 recruited infants, 770 (58.3%) had common cold or acute bronchiolitis on at least one occasion during the study period. Pediatricians prescribed antibiotics at least once in 21.4% of cases diagnosed as the common cold and 45.5% of cases of acute bronchiolitis. Logistic regression analysis revealed that antibiotics misuse was more common among infants born to mothers with lower educational levels (odds ratio [OR] = 1.6; 95% confidence interval [CI]: 1.1-2.3). Furthermore, pediatricians tend to prescribe antibiotics in dispensaries more often than in private clinics (OR = 1.4; 95% CI: 1.0-2.3). CONCLUSION: This study shows a substantial quantity of antibiotics prescriptions for common cold and acute bronchiolitis in our population. Our findings suggest that lower maternal education and pediatricians working in dispensaries (versus private clinics) are associated with increased antibiotics misuse.