What is the use of Doxazosin (alpha-1 adrenergic blocker)?

From the Guidelines

Doxazosin is an alpha-1 adrenergic blocker primarily used to treat high blood pressure and symptoms of benign prostatic hyperplasia (BPH), with a typical starting dose of 1 mg once daily, which can be gradually increased to 2-4 mg daily if needed, with a maximum dose of 16 mg daily for hypertension and 8 mg daily for BPH.

Key Points

• Doxazosin works by relaxing blood vessels and smooth muscle in the prostate and bladder neck, improving blood flow and reducing urinary symptoms 1.
• Common side effects include dizziness, headache, fatigue, and postural hypotension (blood pressure drop when standing), which is why it's often taken at bedtime and started at a low dose 1.
• The first-dose effect can cause significant dizziness or fainting, so patients should avoid driving or hazardous activities after the initial dose 1.
• Doxazosin may take several weeks to reach full effectiveness for BPH symptoms 1.
• Patients should inform their doctor about all medications they take, as doxazosin can interact with erectile dysfunction medications and other antihypertensives, potentially causing dangerous blood pressure drops 1.

Considerations

• According to the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline, alpha-1 blockers like doxazosin are associated with orthostatic hypotension, especially in older adults, and may be considered as second-line agents in patients with concomitant BPH 1.
• The guideline also recommends that patients with hypertension should be advised on healthy lifestyle modification, weight reduction, reduction of sodium intake, increased consumption of fruits, vegetables, and low-fat dairy products, and moderation of alcohol intake 1.
• Doxazosin is not recommended as a first-line agent for hypertension unless the patient has a specific condition that requires its use, such as BPH 1.

From the FDA Drug Label

1.1 Benign Prostatic Hyperplasia (BPH) Doxazosin tablets, USP are indicated for the treatment of the signs and symptoms of BPH.

1. 2 Hypertension Doxazosin tablets, USP are indicated for the treatment of hypertension, to lower blood pressure.

The use of Doxazosin (alpha-1 adrenergic blocker) is for the treatment of:

• Benign Prostatic Hyperplasia (BPH): to improve symptoms such as urinary frequency, nocturia, weak stream, hesitancy, and incomplete emptying.
• Hypertension: to lower blood pressure and reduce the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions 2.

From the Research

Uses of Doxazosin

• Doxazosin is used to treat benign prostatic hyperplasia (BPH) by relaxing prostatic muscle tone and decreasing symptoms 3, 4, 5, 6
• It is also used to treat hypertension, either alone or in combination with other antihypertensive agents 4, 7, 5, 6
• Doxazosin has been shown to improve urinary flow rates and symptoms in patients with BPH, as well as lower blood pressure in patients with hypertension 3, 4, 7, 5, 6

Benefits of Doxazosin

• Doxazosin is effective in treating BPH and hypertension, and is well-tolerated by patients 3, 4, 7, 5, 6
• It can be used as a monotherapy or in combination with other antihypertensive agents 7, 6
• Doxazosin has been shown to improve quality of life in patients with BPH and hypertension 7, 5

Patient Populations

• Doxazosin is suitable for use in patients with mild to moderate hypertension and BPH 7, 6
• It can be used in patients with concomitant hypertension and BPH, and has been shown to be effective in improving symptoms and blood pressure control in these patients 7
• Doxazosin has been shown to be effective and well-tolerated in both older and younger patients 7