Effect of Doxazosin GITS on Blood Pressure in Hypertensive and Normotensive Patients: A Review of Hypertension and BPH Studies

Doxazosin is an effective treatment for patients with hypertension, benign prostatic hyperplasia (BPH) and the two comorbidly. In its standard formulation, doxazosin requires a multistep titration regimen to minimize a possible first-dose effect. A new extended-release gastrointestinal therapeutic system (GITS) formulation of doxazosin was developed to improve the pharmacokinetic profile of the parent compound and to reduce or eliminate the need for dose titration and the potential risk of overdosing. This review presents an analysis of the effect of doxazosin GITS monotherapy on blood pressure (BP) and tolerability, as evaluated in four clinical trials, two conducted in patients with stage 1 to stage 2 hypertension and two in patients with BPH with different levels of BP. Doxazosin GITS was as effective as doxazosin standard and more effective than placebo was in reducing and controlling BP in patients with hypertension. Among normotensive patients with BPH, no clinically significant effect on BP was observed and no episodes of syncope were recorded. Doxazosin GITS was generally better tolerated than doxazosin standard, based on the proportion of patients with adverse events and those withdrawing due to adverse events. Moreover, the GITS formulation eliminated the need for titration in most patients. Doxazosin GITS is an effective and well-tolerated treatment in patients with hypertension and/or BPH and without heart failure or clinical coronary heart disease and has advantages over doxazosin standard in terms of a simpler dosing regimen and improved tolerability.