Gastrooesophageal reflux disease (GERD) is highly prevalent in the Western world but its true population prevalence is difficult to estimate without a validated instrument to detect it. The evaluation of health-related quality of life (HRQoL) is an useful tool in this assessment. The aims of this study are to translate and validate a GERD specific HRQoL questionnaire and evaluate HRQoL in a Brazilian population before and after GERD treatment. GERD patients with typical symptoms and Los Angeles Classes A to C esophagitis were included in the study. Two HRQoL questionnaires and upper digestive endoscopy were performed before and after 6 weeks treatment with pantoprazole 40 mg/day followed by 80 mg/day for another 8 weeks if healing did not occur. A generic (SF-36) and one disease-specific questionnaire (GERD score) were used. The latter was translated and validated for Brazilian Portuguese. From January 2002 to December 2003, 100 patients were enrolled. Of these, 78 patients were evaluated in a per protocol analysis (35 men, mean age: 40 years). The translated questionnaire (Brazilian GERD Score, BGERDS) demonstrated adequate psychometric properties (validity, responsiveness and reliability). SF-36 and BGERDS domains significantly improved after treatment (P < 0.01 and P < 0.001 respectively). The BGERDS was shown to be valid and reliable. Patients with esophagitis showed an impaired HRQoL that improved or normalized after treatment with pantoprazole.