Objective: Automated IVR telephone-based systems are widely used in many aspects of clinical trials, but there is relatively little empirical data to support the use of IVR for collecting patient reported outcomes (PROs) such as daily symptom diaries. We have evaluated IVR in a placebo-controlled study of seasonal rhinitis. Methods: Patients were allocated at random to receive either 200ìg budesonide or placebo for three weeks. All patients received up to 120 mg per day terfenadine as required. Patients dialled into an IVR system each evening. Blocked nose, stuffy nose, runny nose, and eye symptoms were rated by pressing a button on the phone keypad to record severity on the scale 0=absent; 1=mild; 2=moderate; 3=severe. Patients also recorded the number of terfenadine tablets taken. Results: Data were collected from 32 patients (15 male) aged 19-65 years. Patients were able to use the IVR system without difficulty. All four symptoms showed lower average severity over the study period for the budesonide group than for placebo. This was significant for blocked nose (Wilcoxon S = 237, p<0.01); eye symptoms (S = 218; p<0.05); overall symptoms (S = 229, p<0.05). The number of terfenadine tablets taken was also lower in the budesonide group than for placebo (S = 225, p<0.05). Conclusion: These data demonstrate the effects of an established treatment, and thus suggest that IVR is a valid method for collecting PRO data in an unsupervised environment. The application was relatively simple, involving familiar and easily understood symptoms, and response options that were the same for all symptoms. Further research to investigate more complex PRO applications is warranted.