BACKGROUND Quality of life (QOL) issues resulting from participation in an allergy research trial, or indeed any clinical trial, is not documented in the medical literature. OBJECTIVE To determine whether participating in a trial where allergic symptoms are induced has a significant impact on subjects' QOL, and to quantify extent and duration. METHODS Subjects were recruited from a trial utilizing a controlled allergen environment to assess anti-allergic medications. A QOL survey (consisting of the Rhinoconjunctivitis Quality of Life Questionnaire [RQLQ] & the SF-36) was completed at screening, on study day, and approximately 2 weeks post-study. Follow-up was sought from subjects' whose QOL was significantly worse than baseline. RESULTS Of 219 trial participants, 206 completed both screening and study surveys; 141 returned at least one follow-up survey; and 136 constructed the final dataset. Mean overall scores at follow-up via RQLQ were significantly better than screening (P < .001). Significant decreases in QOL from baseline on study day occurred in social function on the SF-36 (P = .026) and in domains of sleep (P = .019), non-nasal symptoms (P = .05), ocular symptoms (P < .001), and nasal symptoms (P < .001) on the RQLQ. Average post-study follow-up was 17.1 days (range = 5 to 55 days). CONCLUSION Subjects participating in a trial involving allergic symptom induction experienced a decrease of QOL in parameters specific to rhinoconjunctivitis and social function. Subjects' QOL returned to or improved over baseline within 2 1/2 weeks. Positive QOL findings are important to studies where symptoms are induced and also have relevance to standard Phase 3 drug trials.