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Usefulness of the alpha1-blocker doxazosin as a third-line antihypertensive drug

Yuko Ohta1, Takuya Tsuchihashi, Uran Onaka

  • 1Division of Hypertension, Clinical Research Center, National Kyushu Medical Center, Fukuoka, Japan. yukoo@qmed.hosp.go.jp

Hypertension Research : Official Journal of the Japanese Society of Hypertension
|June 2, 2007
PubMed

Insights

Adding low-dose doxazosin, an alpha(1)-blocker, significantly improved blood pressure control in hypertensive patients already on combination therapy with calcium channel blockers and either ARBs or ACE inhibitors.

Area of Science:

  • Cardiology
  • Pharmacology
  • Internal Medicine

Background:

  • A significant portion of hypertensive patients exhibit inadequate blood pressure (BP) control despite current treatments.
  • Common combination therapies include calcium channel blockers (CCBs) with angiotensin II (AII) receptor blockers (ARBs) or AII-converting enzyme (ACE) inhibitors.
  • The role of alpha(1)-blockers in such established combination therapies for hypertension remains largely unexplored.

Purpose of the Study:

  • To evaluate the efficacy of adding a low-dose alpha(1)-blocker to existing CCB and ARB/ACE inhibitor combination therapy for hypertension.
  • To assess the impact of doxazosin on BP control in patients with previously insufficient BP management.

Main Methods:

  • A study involving 41 hypertensive patients with poor BP control on CCBs plus ARBs or ACE inhibitors.
  • Low-dose doxazosin (1-2 mg) was added to their existing antihypertensive regimen.
  • Clinical parameters, including BP and blood chemistry, were monitored over a mean follow-up of 170 days.

Main Results:

  • Mean BP decreased significantly from 152/81 mmHg to 135/70 mmHg after adding doxazosin (p<0.001).
  • The prevalence of patients achieving good systolic BP control (<140 mmHg) increased from 24% to 61% (p<0.01).
  • Good diastolic BP control (<90 mmHg) improved from 78% to 98% (p<0.01).

Conclusions:

  • Addition of low-dose doxazosin is an effective strategy for reducing BP in patients with suboptimal control on CCBs and ARBs/ACE inhibitors.
  • Doxazosin demonstrates utility as a third-line antihypertensive agent in this patient population.
  • The findings support the integration of alpha(1)-blockers into advanced combination therapy for resistant hypertension.

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