The objective of this study was to compare quality of life and incidence of dry persistent cough among patients treated with eprosartan and enalapril for mild-moderate hypertension. This was a randomised 26-week double-blind controlled trial carried out in clinics in nine countries of North America, Europe and South Africa. A total of 529 patients aged 18 and over with diastolic blood pressure between 95 mm Hg and 114 mm Hg were studied. Treatment comprised of eprosartan or enalapril monotherapy for 12 weeks with the option of hydrochlorothiazide addition for the remaining 14 weeks. The primary outcome measures were cough and the Psychological General Wellbeing Index (PGWB) total and subscales (anxiety, self-control, depression, general health, positive wellbeing and vitality). The results were that 17.8% of enalapril patients and 13.2% of eprosartan patients withdrew from randomised treatment. Those on enalapril were twice as likely to have gained a definite or possible cough by study end point as those on eprosartan (7.6% vs 3.2%) P = 0.099. At monotherapy end point the differences were greater (9.9% vs 2.1%) and of statistical significance, P = 0.001. Patients treated with enalapril, however, had small but significant improvements in measures of self-control and total PGWB compared with those on eprosartan. The effect sizes of 0.2 or less indicated that there were small differences. In conclusion eprosartan was associated with fewer coughs than enalapril but it performed less well on some aspects of quality of life.