What is the recommended dose, contraindications, drug interactions, adverse effects, monitoring, and alternative therapies for alfuzosin in adult men with benign prostatic hyperplasia?

Alfuzosin for Benign Prostatic Hyperplasia

Recommended Dose

Alfuzosin 10 mg extended-release should be taken once daily immediately after the same meal each day, without dose titration. 1

• The tablet must not be chewed or crushed 1
• Food intake is essential: absorption is 50% lower under fasting conditions 1
• No dose titration is required, unlike doxazosin or terazosin 2, 3
• Symptom relief typically occurs within the first 2 weeks of treatment 4

Contraindications

Alfuzosin is absolutely contraindicated in moderate-to-severe hepatic impairment (Child-Pugh B and C), with potent CYP3A4 inhibitors, and in patients with known hypersensitivity. 1

• Moderate or severe hepatic impairment (Child-Pugh categories B and C) due to increased alfuzosin blood levels 1
• Potent CYP3A4 inhibitors including ketoconazole, itraconazole, and ritonavir, which significantly elevate alfuzosin levels 1
• Known hypersensitivity to alfuzosin hydrochloride or any tablet component 1

Drug Interactions

Avoid all potent CYP3A4 inhibitors when prescribing alfuzosin. 1

• Ketoconazole, itraconazole, and ritonavir are specifically contraindicated due to substantial increases in alfuzosin blood levels 1
• Exercise caution with other antihypertensive agents, though alfuzosin causes only marginal blood pressure changes 4
• Alpha-blockers should not be relied upon for optimal hypertension management; separate antihypertensive therapy may be required 2

Adverse Effects

Alfuzosin carries a lower risk of orthostatic hypotension compared to doxazosin or terazosin, and a lower risk of ejaculatory dysfunction compared to tamsulosin. 2

Common Adverse Events:

• Dizziness/postural dizziness (3.1% in real-world practice) 4
• Asthenia (fatigue) 2
• Nasal congestion from alpha-receptor blockade in nasal vasculature 2
• Ejaculatory dysfunction is uncommon (0.3-0.6%), significantly lower than tamsulosin 4, 5

Cardiovascular Effects:

• Orthostatic hypotension occurs less frequently than with non-selective agents (doxazosin, terazosin) 2
• Asymptomatic orthostatic hypotension incidence is low (2.8%) with no age effect identified 5
• Blood pressure changes remain marginal, even in elderly men and those on antihypertensive co-medication 4

Important Caveat:

• While intraoperative floppy iris syndrome (IFIS) is well-documented with tamsulosin 6, inform ophthalmologists of any alpha-blocker use before cataract surgery

Monitoring

Monitor symptom improvement using the International Prostate Symptom Score (IPSS) and assess for orthostatic symptoms, particularly in the first 2 weeks. 4, 5

• Symptom assessment: Expect IPSS improvement of ≥3 points in 77% of patients and >6 points in 50% by 3 months 4
• Peak flow rate: Anticipate increase from baseline of approximately 2.2 mL/s 5
• Blood pressure: Check for orthostatic changes, especially in elderly patients or those on antihypertensives, though clinically significant changes are rare 4
• Sexual function: Inquire about ejaculatory changes, though incidence is very low 4, 5
• Long-term efficacy: Clinical benefits are maintained for up to 2 years 4

Alternative Therapies

For patients prioritizing sexual function preservation, alfuzosin is preferred over tamsulosin; for those with significant cardiovascular risk, alfuzosin is preferred over doxazosin or terazosin. 2

Other Alpha-Blockers:

• Tamsulosin: Higher ejaculatory dysfunction rate (4.5-14%) but lower orthostatic hypotension risk than doxazosin/terazosin 2, 6
• Doxazosin and terazosin: Require dose titration and carry higher orthostatic hypotension risk 2
• Silodosin: Effective for LUTS but associated with higher ejaculatory dysfunction rates 7

5-Alpha Reductase Inhibitors:

• Dutasteride or finasteride: Consider for men with prostate volume >30-40 mL who need long-term risk reduction for acute urinary retention and surgical intervention 7
• Combination therapy (alpha-blocker + 5-ARI) provides superior symptom improvement in men with prostatic enlargement 7

Non-Pharmacologic Options:

• Watchful waiting: Appropriate for men with mild symptoms (IPSS <8) 7
• Self-management programs: May benefit select patients with uncomplicated LUTS 7