Objectives : To obtain detailed information on current prescribing rates of antibiotics for respiratory tract infections (RTIs) in Dutch general practice and its relation with age and respiratory tract clinical entities. Methods : We assessed the mean proportion of antibiotics prescribed for RTIs per age group, contact-based and population-based using all patient contacts concerning RTIs in the year 2000 selected from the IPCI database, containing information on general practice consultations of 235 290 patients. Results : In one-third of all contacts concerning RTIs, antibiotics were prescribed, with much variation between age groups and clinical entities. For children (0-15 years) and the elderly (over 75 years), the lowest contact-based percentages of prescribed antibiotics for RTIs were found, while population-based, children of age 0-5 years received far more antibiotics for RTIs. High prescribing rates were seen in patients with sinusitis-like complaints (67%) or pneumonia (78%), whereas low rates were found for patients with upper RTIs (16%). Conclusions : Potential over-prescribing of antibiotics for RTIs occurs in the age group 31-65 years, not in children and the elderly, and in patients with upper RTIs, sinusitis and most likely acute bronchitis (contact-based). The management of these subgroups of patients should be addressed in quality assurance programmes. Children and the elderly visit the GP much more often than adults, which can be explained by more frequent (children) or more severe (elderly) RTI morbidity, but in proportion they do not receive more antibiotics.