BACKGROUND: Many recent efforts to reduce unnecessary medical services have targeted care of upper respiratory infections (URIs). We tested whether patients who seek care very early in their illness differ from those who seek care later and whether they might require a different approach to care. METHODS: We surveyed by telephone 257 adult patients and 249 parents of child patients who called or visited one of 3 primary care clinics within 10 days (adults) or 14 days (parents) of the onset of uncomplicated URI symptoms. Those who contacted the clinic within the first 2 days of illness were compared with those who made contact later. RESULTS: Although 28% of adults and 41% of parents contacted their clinic within the first 2 days of symptom onset, we found very few differences in the characteristics of the caller or patient between those who called early and later. The illnesses of those who called early were not more severe, and they did not have different beliefs, histories, approaches to medical care, or needs. The only clinician-relevant difference was that adult patients calling in the first 2 days had a greater desire to rule out complications (84.7% vs 64.1% calling in 3-5 days and 70.6% calling after 5 days of illness, P < or = .05). CONCLUSIONS: Those who seek medical care very early for a URI do not appear to be different in clinically important ways. If we are going to reduce overuse of medical care and antibiotics for URIs, clinical trials of more effective and efficient strategies are needed to encourage home care and self-management.