Five classes of antihypertensive drugs have proven efficacy in the prevention of cardiovascular morbidity and mortality. Among the remaining antihypertensives, the action of alpha-1-blockers is supported by most clinical evidence; however, in combination therapy, the published data concern their use as third-line drugs at the most. The data from patients with drug-resistant hypertension remain limited. The aim of our study was to evaluate the efficacy and safety of doxazosin in this clinical setting. Data from 97 patients with resistant hypertension treated by doxazosin were analysed retrospectively. Doxazosin was usually added as the fifth antihypertensive drug in individuals who were either unresponsive to or intolerant of the combination of other antihypertensives. The dose of doxazosin ranged from 2 to 16 mg/day. The mean duration of follow-up was 21+/-17 months. Adverse events related to doxazosin treatment were rare and led to discontinuation of the therapy in only five patients (5.2%). Data from 34 patients were subjected to analysis of efficacy. In this subgroup, doxazosin therapy led to the reduction of blood pressure from 159+/-20/92+/-14 to 126+/-16/73+/-10 mmHg. We found that doxazosin is a well-tolerated and effective drug for patients with resistant arterial hypertension who require a combination of multiple antihypertensive drugs.