Brand name: Uroxatral
Drug class: Selective alpha-1-Adrenergic Blocking Agents
VA class: HS900
Chemical name: N-[3-[(4-Amino-6,7-dimethoxy-2-quinazolinyl)methylamino]propyl]tetrahydro-2-furancarboxamide monohydrochloride
Molecular formula: C₁₉H₂₇N₅O₄•HCl
CAS number: 81403-68-1

Medically reviewed by Drugs.com on Mar 22, 2024. Written by ASHP.

Introduction

α₁-Adrenergic blocker; quinazoline derivative;^{1 2} structurally and pharmacologically related to prazosin.^{1 2 3}

Uses for Alfuzosin

Benign Prostatic Hyperplasia (BPH)

Reduction of urinary obstruction and relief of associated manifestations (e.g., hesitancy, interrupted or weak stream, sensation of incomplete bladder emptying or straining, urgency, nocturia) in patients with symptomatic BPH.^{1 2 3}

Although drug therapy usually is not as effective as surgical therapy, it may provide adequate symptomatic relief with fewer and less serious adverse effects compared with surgery.¹⁴

May consider combined therapy with an α₁-adrenergic blocker and 5α-reductase inhibitor for men with bothersome moderate to severe BPH and demonstrable prostatic enlargement.¹⁴ Has been more effective than therapy with either drug alone in preventing long-term BPH symptom progression.¹⁴ Men at risk for BPH progression are most likely to benefit from combination therapy.¹⁴

Other Uses

Manufacturer states that alfuzosin should not be used for the treatment of hypertension.¹

Alfuzosin Dosage and Administration

Administration

Oral Administration

Administer orally once daily immediately after the same meal each day.¹

Do not chew or crush tablets.¹

Dosage

Available as alfuzosin hydrochloride; dosage is expressed in terms of the salt.¹

Adults

BPH

Oral

10 mg daily.¹

Related/similar drugs

tamsulosin, finasteride, tadalafil, Flomax, prazosin, Cialis

Cautions for Alfuzosin

Contraindications

• Moderate or severe hepatic impairment (Child-Pugh class B or C).¹

• Concomitant use with potent inhibitors of CYP3A4 (e.g., itraconazole, ketoconazole, ritonavir).¹

• Known hypersensitivity to alfuzosin or any ingredient in the formulation.¹

Warnings/Precautions

Warnings

Postural Hypotension

Potential for postural hypotension, dizziness, or syncope.¹

Administer with caution in patients with symptomatic hypotension or those who have had a hypotensive response to other drugs.¹

General Precautions

Prostate Cancer

Exclude possibility of prostate cancer prior to initiation of therapy.¹

Intraoperative Floppy Iris Syndrome

Intraoperative floppy iris syndrome (IFIS) observed during phacoemulsification cataract surgery in some patients currently receiving or previously treated with α₁-adrenergic blocking agents.¹

If patient has received α₁-adrenergic blockers, ophthalmologist should be prepared to modify the surgical technique (e.g., through use of iris hooks, iris dilator rings, or viscoelastic substances) to minimize complications of IFIS.¹ There does not appear to be a benefit from discontinuing α₁-blocker therapy prior to cataract surgery.¹

Coronary Insufficiency

If new or worsening symptoms of angina pectoris occur, discontinue therapy.¹

Congenital or Acquired QT-Interval Prolongation

Modest QT-interval prolongation possible.¹

Consider potential for QT-interval prolongation in patients with known history of QT-interval prolongation and/or in those receiving concomitant therapy with drugs known to prolong QT interval.¹

Specific Populations

Pregnancy

Category B.¹

Not indicated for use in women.¹

Lactation

Not indicated for use in women.¹

Pediatric Use

Not indicated for use in children.¹

Geriatric Use

No substantial differences in safety and efficacy relative to younger adults.¹

Hepatic Impairment

Use not recommended in patients with moderate to severe hepatic impairment.¹ Not studied in patients with mild hepatic impairment.¹

Renal Impairment

Use with caution in patients with severe renal impairment.¹

Common Adverse Effects

Dizziness, headache, fatigue, upper respiratory tract infection.¹

Drug Interactions

Extensively metabolized by CYP3A4.¹

Drugs Affecting Hepatic Microsomal Enzymes

Pharmacokinetic interaction with potent inhibitors of CYP3A4 (increased plasma alfuzosin concentrations).¹ Concomitant use contraindicated.¹

Specific Drugs

Alfuzosin Pharmacokinetics

Absorption

Bioavailability

Absolute bioavailability of 49% following oral administration under fed conditions.¹ Peak plasma concentration attained in about 8 hours.¹

Food

Food increases extent of absorption by 50%.¹

Distribution

Plasma Protein Binding

82–90%.¹

Elimination

Metabolism

Extensively metabolized in the liver via oxidation, O-demethylation, and/or N-dealkylation to form pharmacologically inactive metabolites.¹

CYP3A4 is the principal hepatic isoenzyme involved in the drug’s metabolism.¹

Elimination Route

Excreted in feces (69%) and urine (24%) as unchanged drug and metabolites.¹

Half-life

10 hours.¹

Special Populations

In patient with moderate to severe hepatic impairment, plasma alfuzosin concentrations are 3- to 4-fold higher than in healthy individuals; pharmacokinetics not studied in patients with mild hepatic impairment.¹

In patient with mild to severe renal impairment, AUC is 50% higher than in healthy individuals.¹

Stability

Storage

Oral

Tablets

25°C (may be exposed to 15–30°C).¹ Protect from moisture and light.¹

Actions

• Blocks α₁-adrenergic receptors in the lower urinary tract to cause relaxation of smooth muscle in the bladder neck and prostate and improve symptoms of BPH (e.g., urine flow).¹

Advice to Patients

• Risk of feeling faint or dizzy, particularly following initiation of therapy; avoid situations where injury could result if syncope occurs.¹

• Importance of exercising caution when driving or operating machinery.¹

• Importance of taking alfuzosin exactly as prescribed.¹ Importance of taking alfuzosin with the same meal each day and of not chewing or crushing the tablets.¹

• Importance of advising male patients being considered for cataract surgery that they should inform their ophthalmologist of current or prior α₁-blocker (e.g., alfuzosin) therapy.¹

• Importance of women informing their clinician if they are or plan to become pregnant or plan to breast-feed.¹

• Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs, as well as concomitant illnesses.¹

• Importance of informing patients of other important precautionary information.¹ (See Cautions.)

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

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