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Pronunciation
(al FYOO zoe sin)
Generic Available (U.S.)
Yes
Index Terms
Brand Names: U.S.
Brand Names: Canada
Pharmacologic Category
Pharmacologic Category Synonyms
Use: Labeled Indications
Treatment of the functional symptoms of benign prostatic hyperplasia (BPH)
Use: Unlabeled
Facilitation of expulsion of ureteral stones
Pregnancy Risk Factor
B
Pregnancy Considerations
Teratogenic effects were not observed in animal studies.
Contraindications
Hypersensitivity to alfuzosin or any component of the formulation; moderate or severe hepatic insufficiency (Child-Pugh class B and C); concurrent use with potent CYP3A4 inhibitors (eg, itraconazole, ketoconazole, ritonavir) or other alpha1-blocking agents
Warnings/Precautions
Concerns related to adverse effects:
• Angina: Discontinue if symptoms of angina occur or worsen.
• Floppy iris syndrome: Intraoperative floppy iris syndrome has been observed in cataract surgery patients who were on or were previously treated with alpha1-blockers; causality has not been established and there appears to be no benefit in discontinuing alpha-blocker therapy prior to surgery.
• Orthostatic hypotension/syncope: May cause significant orthostatic hypotension and syncope, especially with first dose; anticipate a similar effect if therapy is interrupted for a few days, if dosage is rapidly increased, or used with antihypertensives (particularly vasodilators), PDE-5 inhibitors, nitrates or other medications which may result in hypotension. Patients should be cautioned about performing hazardous tasks when starting new therapy or adjusting dosage upward.
• Priapism: Priapism has been associated with use (rarely).
Disease-related concerns:
• Hepatic impairment: Use with caution in patients with mild hepatic impairment; contraindicated in moderate-to-severe impairment.
• Prostate cancer: Rule out prostatic carcinoma before beginning therapy (many symptoms of BPH and prostate cancer are similar).
• QT prolongation: Alfuzosin has been shown to prolong the QT interval alone (minimal) and with other drugs with comparable effects on the QT interval (additive). Use with caution in patients with known QT prolongation (congenital or acquired).
• Renal impairment: Use with caution in patients with severe renal impairment (Clcr <30 mL/minute).
Concurrent drug therapy issues:
• High potential for interactions: Contraindicated in patients receiving strong CYP3A4 inhibitors or other alpha1-blockers.
Other warning/precautions:
• Antihypertensive agent: Not intended for use as an antihypertensive drug.
Adverse Reactions
1% to 10%:
Central nervous system: Dizziness (6%), fatigue (3%), headache (3%), pain (1% to 2%)
Gastrointestinal: Abdominal pain (1% to 2%), constipation (1% to 2%), dyspepsia (1% to 2%), nausea (1% to 2%)
Genitourinary: Impotence (1% to 2%)
Respiratory: Upper respiratory tract infection (3%), bronchitis (1% to 2%), pharyngitis (1% to 2%), sinusitis (1% to 2%)
<1%: Hypotension, postural hypotension, syncope
Postmarketing and/or case reports: Angina pectoris (pre-existing CAD), angioedema, atrial fibrillation, chest pain, cholestatic liver injury, diarrhea, edema, flushing, intraoperative floppy iris syndrome (with cataract surgery), priapism, pruritus, rash, rhinitis, tachycardia, urticaria
Metabolism/Transport Effects
Substrate of CYP3A4 (major); Note: Assignment of Major/Minor substrate status based on clinically relevant drug interaction potential
Drug Interactions
Alpha1-Blockers: May enhance the antihypertensive effect of other Alpha1-Blockers. Risk X: Avoid combination
Antihypertensives: Alfuzosin may enhance the hypotensive effect of Antihypertensives. Risk C: Monitor therapy
Beta-Blockers: May enhance the orthostatic hypotensive effect of Alpha1-Blockers. The risk associated with ophthalmic products is probably less than systemic products. Exceptions: Levobunolol; Metipranolol. Risk D: Consider therapy modification
Calcium Channel Blockers: Alpha1-Blockers may enhance the hypotensive effect of Calcium Channel Blockers. Risk C: Monitor therapy
CYP3A4 Inducers (Strong): May increase the metabolism of CYP3A4 Substrates. Risk C: Monitor therapy
CYP3A4 Inhibitors (Moderate): May decrease the metabolism of CYP3A4 Substrates. Risk C: Monitor therapy
CYP3A4 Inhibitors (Strong): May increase the serum concentration of Alfuzosin. Risk X: Avoid combination
Deferasirox: May decrease the serum concentration of CYP3A4 Substrates. Risk C: Monitor therapy
Herbs (CYP3A4 Inducers): May increase the metabolism of CYP3A4 Substrates. Risk C: Monitor therapy
Ivacaftor: May increase the serum concentration of CYP3A4 Substrates. Risk C: Monitor therapy
MAO Inhibitors: May enhance the orthostatic hypotensive effect of Orthostatic Hypotension Producing Agents. Risk C: Monitor therapy
Nitroglycerin: Alfuzosin may enhance the hypotensive effect of Nitroglycerin. Risk C: Monitor therapy
Phosphodiesterase 5 Inhibitors: May enhance the hypotensive effect of Alpha1-Blockers. Management: Ensure patient is stable on one agent prior to initiating the other, and always initiate combination using the lowest possible dose of the drug being added. When tadalafil is used for treatment of BPH, concurrent alpha 1-blockers are not recommended. Risk D: Consider therapy modification
Protease Inhibitors: May increase the serum concentration of Alfuzosin. Risk X: Avoid combination
QTc-Prolonging Agents: Alfuzosin may enhance the QTc-prolonging effect of QTc-Prolonging Agents. Risk C: Monitor therapy
Telaprevir: May increase the serum concentration of Alfuzosin. Risk X: Avoid combination
Tocilizumab: May decrease the serum concentration of CYP3A4 Substrates. Risk C: Monitor therapy
Ethanol/Nutrition/Herb Interactions
Food: Food increases the extent of absorption. Management: Administer immediately following a meal at the same time each day.
Herb/Nutraceutical: St John's wort may decrease alfuzosin levels. Management: Avoid St John's wort.
Storage
Store at room temperature of 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F). Protect from light and moisture.
Mechanism of Action
An antagonist of alpha1-adrenoreceptors in the lower urinary tract. Smooth muscle tone is mediated by the sympathetic nervous stimulation of alpha1-adrenoreceptors, which are abundant in the prostate, prostatic capsule, prostatic urethra, and bladder neck. Blockade of these adrenoreceptors can cause smooth muscles in the bladder neck and prostate to relax, resulting in an improvement in urine flow rate and a reduction in BPH symptoms.
Pharmacodynamics/Kinetics
Absorption: Decreased 50% under fasting conditions
Distribution: Vd: 3.2 L/kg
Protein binding: 82% to 90%
Metabolism: Hepatic, primarily via CYP3A4; metabolism includes oxidation, O-demethylation, and N-dealkylation; forms metabolites (inactive)
Bioavailability: 49% following a meal
Half-life elimination: 10 hours
Time to peak, plasma: 8 hours following a meal
Excretion: Feces (69%); urine (24%; 11% as unchanged drug)
Dosage
Oral: Adults:
Benign prostatic hyperplasia (BPH): 10 mg once daily
Ureteral stones, expulsion (unlabeled use): 10 mg once daily, discontinue after successful expulsion (average time to expulsion 1-2 weeks) (Agrawal, 2009; Ahmed, 2010; Gurbuz, 2011). Note: Patients with stones >10 mm were excluded from studies.
Dosage adjustment in renal impairment: Bioavailability and maximum serum concentrations are increased by ~50% with mild (Clcr 60-80 mL/minute), moderate (Clcr 30-59 mL/minute), or severe (Clcr <30 mL/minute) renal impairment.
Note: Safety data is limited in patients with severe renal impairment (Clcr <30 mL/minute). Use with caution.
Dosage adjustment in hepatic impairment:
Mild hepatic impairment: Use has not been studied; use caution
Moderate or severe hepatic impairment (Child-Pugh class B and C): Clearance is decreased 1/3 to 1/4 and serum concentration is increased three- to fourfold; use is contraindicated
Administration: Oral
Tablet should be swallowed whole; do not crush or chew. Administer once daily (immediately following a meal); should be taken at the same time each day.
Monitoring Parameters
Urine flow, blood pressure, PSA
Dietary Considerations
Take immediately following a meal at the same time each day.
Patient Education
Take at the same time each day. May cause drowsiness, dizziness, postural hypotension, nausea, or sexual dysfunction (reversible, may resolve with continued use). Report altered CNS status (eg, fatigue), severe dizziness or passing out, or erection that lasts more than 4 hours.
Geriatric Considerations
Alfuzosin is a functionally uroselective alpha-blocker, therefore, having minimal effects on the cardiovascular system. Alfuzosin has been available in Europe for many years and appears to be well tolerated in elderly. In one study, orthostatic changes were minimal and not influenced by age.
Dental Health: Effects on Dental Treatment
No significant effects or complications reported
Dental Health: Vasoconstrictor/Local Anesthetic Precautions
No information available to require special precautions
Mental Health: Effects on Mental Status
May cause dizziness
Mental Health: Effects on Psychiatric Treatment
Alfuzosin may cause orthostasis. Concomitant use with psychotropics may produce additive effects on blood pressure. Use caution with thioridazine and ziprasidone; may prolong QT interval. Use caution with nefazodone; may increase levels of alfuzosin resulting in toxicity.
Nursing: Physical Assessment/Monitoring
Obtain thorough medication list to make sure patient is not taking similar medications. Doses may need to be adjusted with history of QT prolongation, CAD, hypotension, or if taking HIV medications. Patients are at risk for dizziness and fainting. Monitor their fluid volume status if taking diuretics or with episodes of excessive vomiting, diarrhea, or sweating. Instruct patients that medications need to taken whole, not broken or crushed, to avoid orthostatic hypotension.
Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet, extended release, oral, as hydrochloride: 10 mg
Uroxatral®: 10 mg
Pricing: U.S. (www.drugstore.com)
Tablet, 24-hour (Alfuzosin HCl)
10 mg (30): $45.99
Tablet, 24-hour (Uroxatral)
10 mg (30): $142.99
References
Agrawal M, Gupta M, Gupta A, et al, “Prospective Randomized Trial Comparing Efficacy of Alfuzosin and Tamsulosin in Management of Lower Ureteral Stones,” Urology, 2009, 73(4):706-9.
Ahmed AF and Al-Sayed AY, “Tamsulosin versus Alfuzosin in the Treatment of Patients with Distal Ureteral Stones: Prospective, Randomized, Comparative Study,” Korean J Urol, 2010, 51(3):193-7.
Gurbuz MC, Polat H, Canat L, et al, “Efficacy of Three Different Alpha 1-Adrenergic Blockers and Hyoscine N-butylbromide for Distal Ureteral Stones,” Int Braz J Urol, 2011, 37(2):195-202.
International Brand Names
Lexi-Comp.com
Last full review/revision March 2012
Content last modified March 2012
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