Alfuzosin

What it is

Alfuzosin is a synthetic quinazoline-derived medicine taken by mouth as a 10 mg extended-release tablet, and its active ingredient is alfuzosin hydrochloride. It belongs to the alpha blockers, and it is described as selective for the alpha1-adrenoreceptors in the lower urinary tract. It is licensed for the signs and symptoms of benign prostatic hyperplasia and for nothing else. The label states explicitly that it is not for high blood pressure and not for children.

What the research says

The evidence for the one approved use is real but modest and mostly short-term. A systematic review of 11 trials in 3,901 men found alfuzosin improved symptom scores more than placebo by 1.8 points on a 35-point scale, with trials lasting only 4 to 26 weeks. Over two years it reduced overall clinical progression of benign prostatic hyperplasia but did not reduce acute urinary retention, which was the trial's primary endpoint. Off-label, it increases the chance of voiding successfully after a catheter is removed in acute retention, and for ureteric stones the placebo-controlled evidence for alpha blockers as a class is null overall and positive only for stones in the lower ureter. Dizziness is the commonest adverse effect, roughly doubled against placebo.

Evidence grade: Limited evidence.

How it works

Drug class: Selective alpha1-adrenergic receptor antagonist (alpha blocker), quinazoline class

Alfuzosin is a selective antagonist of post-synaptic alpha1-adrenoreceptors, which the label locates in the prostate, bladder base, bladder neck, prostatic capsule and prostatic urethra. Blocking them lets that smooth muscle relax, which widens the outflow; in the patient leaflet’s plainer words it may help to relax the muscles in the prostate and the bladder, which may lessen the symptoms of BPH and improve urine flow. It does not shrink the prostate; it only changes the muscle tone around it. The same receptor blockade on blood vessels is why the label’s leading harm is a fall in blood pressure on standing. (Source 1)

What it is used for

• Across 11 randomised trials in 3,901 men, alfuzosin improved the International Prostate Symptom Score more than placebo, with a weighted mean difference of 1.8 points. The trials were short, 4 to 26 weeks, and the systematic review's own conclusion is limited to short-term benefit. Evidence: established. (Source 2)
• In the two-year ALTESS trial, alfuzosin reduced a composite of symptom deterioration, surgery and acute urinary retention from 22.1% to 16.3%, but it did not reduce acute urinary retention, which was the pre-specified primary endpoint. The composite was driven by symptom deterioration, a post hoc endpoint. Evidence: limited. (Source 3)
• In a double-blind placebo-controlled trial, more men voided successfully after the catheter was removed on alfuzosin than on placebo, 61.9% versus 47.9%. The need for surgery at six months, the trial's primary endpoint, was not significantly different. Evidence: limited. (Source 4)
• A meta-analysis of eight placebo-controlled trials of alpha blockers as a class, alfuzosin among them, found no significant effect on overall stone clearance and a benefit only in the subgroup with distal stones. One small three-arm randomised trial found alfuzosin better than placebo for lower ureteric stones and statistically indistinguishable from tamsulosin. Evidence: not-supported. (Source 5)
• The systematic review included two trials against other alpha blockers and one against finasteride and against the combination. Symptom and flow improvements were described as generally comparable to combination therapy and to other alpha1-blockers, and the review's authors called for long-term studies combining alfuzosin with a 5-alpha-reductase inhibitor, which is to say they did not exist. Evidence: limited. (Source 2)
• The label states twice, once in the Highlights and once in the body, that alfuzosin is not indicated for the treatment of hypertension, even though it lowers blood pressure as a side effect. Evidence: not-supported. (Source 6)

Interactions

• Potent CYP3A4 inhibitors: ketoconazole, itraconazole, ritonavir (pharmacokinetic study): Alfuzosin is broken down by the liver enzyme CYP3A4. Blocking that enzyme raises alfuzosin blood levels several-fold, and the combination is contraindicated, not merely cautioned. Ketoconazole 400 mg/day raised peak concentration 2.3-fold and exposure 3.2-fold; even 200 mg/day raised them 2.1-fold and 2.5-fold. (Source 7)
• Grapefruit and grapefruit juice (theoretical): Grapefruit juice inhibits CYP3A4, which is the enzyme that clears alfuzosin, so the interaction is expected on mechanism. We must be plain about the evidence: the US label does not name grapefruit anywhere, and we found no published pharmacokinetic study of grapefruit juice with alfuzosin. What is documented is the contraindication for potent CYP3A4 inhibitors as a class, with ketoconazole as the measured example. Treat the grapefruit concern as extrapolation from that mechanism, not as a measured interaction. (Source 8)
• A meal (food in general) (pharmacokinetic study): Food is not a hazard here, it is a requirement. Absorption is 50% lower on an empty stomach, so the label asks for the tablet to be taken with food and with the same meal each day. Taking it fasting gives roughly half the intended exposure. (Source 9)
• Alcohol (theoretical): Alcohol lowers blood pressure and can worsen light-headedness on standing, so the combination is plausibly additive, but we have to report what the evidence actually is: the US label contains no alcohol interaction statement at all, and we found no study of alcohol with alfuzosin. What the label does document is an increased risk of hypotension, postural hypotension and syncope when alfuzosin is combined with other blood-pressure-lowering products, and advice to avoid situations where injury could follow a faint. (Source 10)
• Antihypertensive medicines and nitrates (label): Both lower blood pressure by a different route, so adding alfuzosin raises the risk of fainting. Between a fifth and a third of men in the pivotal trials were already on an antihypertensive, which is the context for the orthostatic figures in those trials. (Source 10)
• Other alpha adrenergic antagonists (label): The label's position is that alfuzosin should not be combined with another alpha blocker, because the blood-pressure-lowering effects stack. (Source 11)
• PDE5 inhibitors (sildenafil, tadalafil, vardenafil) (label): Both classes are vasodilators, so used together they can lower blood pressure further in some patients, and the label addresses this in its own interaction subsection. (Source 12)
• Herbal supplements that act on CYP3A4, such as St John's wort (an inducer) or grapefruit-derived extracts (inhibitors) (theoretical): Alfuzosin's clearance runs through CYP3A4, so a supplement that induces that enzyme would be expected to lower alfuzosin levels and one that inhibits it to raise them. We must be plain that this is reasoning from the pathway, not a measured finding: the US label names no supplement anywhere, lists no CYP3A4 inducers at all, and we found no published study of any supplement with alfuzosin. The only measured CYP3A4 interaction on the label is ketoconazole, and the only documented position is the class-level contraindication for potent inhibitors. (Source 8)
• Medicines that prolong the QT interval (pharmacokinetic study): Alfuzosin itself produces a small QT change. The label asks for caution in people with acquired or congenital QT prolongation or taking QT-prolonging medicines, and a post-marketing study found that combining alfuzosin with another drug of similar QT effect produced a larger effect than either alone, though not more than additive. (Source 13)

Stopping it

• No withdrawal syndrome, rebound effect or taper is described for alfuzosin in the label or in the trials we read. There is one situation where the label actively tells prescribers to stop: if symptoms of angina appear or worsen, alfuzosin is to be discontinued. (Source 13)
• Stopping before cataract surgery is the case where intuition is wrong. Floppy iris syndrome has been seen in people previously treated as well as currently treated, and the label states there does not appear to be a benefit in stopping beforehand; the counselling section instead asks patients to tell the ophthalmologist, even if they are no longer taking it. (Source 14)
• In acute urinary retention, the one trial that looked at duration concluded the opposite of stopping: its authors said alfuzosin should be continued beyond the acute phase. That conclusion rests on one-month and three-month differences, with the six-month comparison not significant, so it is a weak basis for a stopping rule. (Source 15)
• One symptom is an emergency rather than a reason to stop and wait. The patient leaflet says alfuzosin can cause a painful erection that will not go away (priapism) and that if this happens the person should get medical help right away, because untreated priapism can leave permanent loss of erectile function. The Highlights list of warnings and precautions does not carry a priapism bullet even though section 5.7 of the same label does, so this instruction is easy to miss. (Source 16)

What goes wrong

Dizziness, upper respiratory tract infection, headache and fatigue were the only adverse reactions reaching 2% and exceeding placebo in the three placebo-controlled trials. (Source 17)

• Randomized trial, Moderate certainty.
• Size: 3 placebo-controlled trials involving 1,608 men; 473 received the 10 mg extended-release tablet and 678 received placebo.
• Who: men with benign prostatic hyperplasia in 3-month placebo-controlled trials.
• How long: 3 months.
• Result: dizziness 27 of 473 (5.7%) versus 19 of 678 (2.8%), an absolute increase of 2.9 percentage points and a number needed to harm of about 35; upper respiratory tract infection 14 (3.0%) versus 4 (0.6%); headache 14 (3.0%) versus 12 (1.8%); fatigue 13 (2.7%) versus 12 (1.8%); withdrawal for adverse reactions 4% versus 3%.
• Funding: manufacturer trials reported in the regulator-approved label.

Limit of this finding: The three trials enrolled 1,608 men, but the table has only two columns, placebo (678) and alfuzosin 10 mg (473), which come to 1,151. The rest were on a 15 mg dose the label mentions but does not tabulate, so this table is not a breakdown of all 1,608 men.

Dizziness 19 (2.8%) 27 (5.7%) Upper respiratory tract infection 4 (0.6%) 14 (3.0%) Headache 12 (1.8%) 14 (3.0%) Fatigue 12 (1.8%) 13 (2.7%)

Symptomatic low blood pressure on standing and syncope occurred in a small number of men on alfuzosin and in none on placebo, but a measured positive orthostatic test was no more common on alfuzosin. (Source 18)

• Randomized trial, Moderate certainty.
• Size: 473 alfuzosin and 678 placebo patients in the 3-month trials; blood pressure testing in 469 and 674.
• Who: men in the double-blind phase 3 trials, of whom approximately 20% to 30% were taking antihypertensive medication.
• How long: 3 months.
• Result: hypotension or postural hypotension 2 of 473 (0.4%) versus 0 of 678; syncope 1 (0.2%) versus 0; decreased systolic blood pressure to 90 mm Hg or below with a fall of 20 mm Hg or more in 1 of 469 (0.2%) versus none of 674; a positive orthostatic test in 31 of 473 (6.6%) on alfuzosin versus 52 of 678 (7.7%) on placebo.
• Funding: manufacturer trials reported in the regulator-approved label.

Limit of this finding: The label's own table and its blood pressure testing paragraph point in opposite directions: reported symptomatic hypotension and syncope were more frequent on alfuzosin, but the measured orthostatic test was slightly more frequent on placebo. A reader should not conclude from the 6.6% versus 7.7% figures that alfuzosin does not cause postural hypotension, nor from the 0.4% figure that it commonly does. The label also gives two different group sizes for the same three trials - 678 and 473 in the table, 674 and 469 in the blood-pressure testing paragraph - and never explains the difference, so neither set of denominators can be taken as exact.

Hypotension or postural hypotension 0 2 (0.4%) Syncope 0 1 (0.2%) Testing for blood pressure changes or orthostatic hypotension was conducted in three controlled studies. Decreased systolic blood pressure (≤90 mm Hg, with a decrease ≥20 mm Hg from baseline) was observed in none of the 674 placebo patients and 1 (0.2%) of the 469 UROXATRAL patients. Decreased diastolic blood pressure (≤50 mm Hg, with a decrease ≥15 mm Hg from baseline) was observed in 3 (0.4%) of the placebo patients and in 4 (0.9%) of the UROXATRAL patients. A positive orthostatic test (decrease in systolic blood pressure of ≥20 mm Hg upon standing from the supine position) was seen in 52 (7.7%) of placebo patients and in 31 (6.6%) of the UROXATRAL patients.

Intraoperative floppy iris syndrome has been observed during cataract surgery in people taking or previously taking an alpha blocker, and stopping the drug beforehand does not appear to help. (Source 14)

• Official position, Certainty not rated.
• Size: not quantified in the label.
• Who: people on or previously treated with alpha adrenergic antagonists undergoing cataract surgery.
• How long: indefinite; the label's counselling section says to tell the ophthalmologist even if the patient is no longer taking the drug.
• Result: no rate given; the label describes a flaccid iris that billows, progressive intraoperative miosis despite preoperative dilation, and potential iris prolapse toward the incisions.
• Funding: regulator-approved product label (a position, dated 2025)

This variant of small pupil syndrome is characterized by the combination of a flaccid iris that billows in response to intraoperative irrigation currents, progressive intraoperative miosis despite preoperative dilation with standard mydriatic drugs, and potential prolapse of the iris toward the phacoemulsification incisions. The patient's ophthalmologist should be prepared for possible modifications to their surgical technique, such as the utilization of iris hooks, iris dilator rings, or viscoelastic substances. There does not appear to be a benefit of stopping alpha adrenergic antagonist therapy prior to cataract surgery.

Serious but rare harms reported after marketing include hepatocellular and cholestatic liver injury, priapism, toxic epidermal necrolysis, angioedema, atrial fibrillation and thrombocytopenia. (Source 19)

• Case series, Very low certainty.
• Size: spontaneous reports from a population of uncertain size.
• Who: people taking alfuzosin after approval.
• How long: post-approval surveillance.
• Result: no rates can be calculated; the label states it is not always possible to estimate frequency or establish causation.
• Funding: regulator-approved product label (a position, dated 2025)

Hepatobiliary disorders: hepatocellular and cholestatic liver injury (including cases with jaundice leading to drug discontinuation) Respiratory system disorders: rhinitis Reproductive system disorders: priapism Skin and subcutaneous tissue disorders: rash, pruritis, urticaria, angioedema, toxic epidermal necrolysis Vascular disorders: flushing Blood and lymphatic system disorders: thrombocytopenia

A thorough QT study found a small QT prolongation with alfuzosin that was dose-related and smaller than the moxifloxacin active control, with no Torsade de Pointes signal in post-marketing use. (Source 20)

• Randomized trial, Low certainty.
• Size: 45 healthy white male subjects aged 19 to 45, four-way crossover.
• Who: healthy men given single doses of 10 mg and 40 mg alfuzosin, placebo, and moxifloxacin 400 mg.
• How long: single dose, measured at peak plasma concentration.
• Result: Fridericia-corrected QT change from baseline relative to placebo 4.9 msec (95% CI 0.9, 8.8) at 10 mg and 7.7 msec (1.9, 13.5) at 40 mg, versus 12.7 msec (8.6, 16.8) for moxifloxacin; subject-specific correction gave 1.8 msec (-1.3, 5.0) and 4.3 msec (-0.5, 9.2); heart rate rose 5.2 beats/minute at 10 mg and 5.8 at 40 mg.
• Funding: manufacturer study reported in the regulator-approved label.

Limit of this finding: The table prints a different answer depending on which heart-rate correction is used, and the uncorrected QT actually shortened. The label states no single correction method is known to be more valid and that the study was not designed for direct statistical comparison between drugs or doses, so a reader cannot read any one of these numbers as the effect. In the label's Table 3 the Moxifloxacin row prints a footnote marker on the dose cell; the marker means "Active control", which is the definition printed at the foot of the table. It is not part of the dose.

Alfuzosin 10 mg -5.8 (-10.2, -1.4) 4.9 (0.9, 8.8) 1.8 (-1.4, 5.0) 1.8 (-1.3, 5.0) Alfuzosin 40 mg -4.2 (-8.5, 0.2) 7.7 (1.9, 13.5) 4.2 (-0.6, 9.0) 4.3 (-0.5, 9.2) Moxifloxacin *400 mg 6.9 (2.3, 11.5) 12.7 (8.6, 16.8) 11.0 (7.0, 15.0) 11.1 (7.2, 15.0) * Active control

A post-marketing study found that taking alfuzosin together with another QT-prolonging medicine increased the QT interval more than either drug alone, and the label says the clinical impact is unknown. (Source 21)

• Blood level study, Low certainty.
• Size: not stated in the label.
• Who: post-marketing QT study participants, number not given.
• How long: single-dose QT assessment.
• Result: placebo-subtracted QTcF increase 1.9 msec (upper bound 95% CI 5.5 msec) for alfuzosin 10 mg alone and 5.9 msec (upper bound 95% CI 9.4 msec) for the two drugs together, which the label says was not more than additive; the positive control moxifloxacin 400 mg gave 10.2 msec (upper bound 95% CI 13.8 msec)
• Funding: manufacturer study reported in the regulator-approved label.

Limit of this finding: The label gives no design for this study beyond "a separate post-marketing QT study": it does not name the other drug, does not give the number of participants, and states the study was not designed for direct statistical comparison between drugs. It is recorded here as a small human measurement study rather than a randomised trial, because the taxonomy has no value for a pharmacodynamic QT study and the label does not say it was randomised. The same paragraph says the clinical impact of these QTc changes is unknown, so this is a measured electrical change and not a measured rate of harm.

The concomitant administration of the two drugs showed an increased QT effect when compared with either drug alone. This QTcF increase [5.9 msec (UB 95% CI, 9.4 msec)] was not more than additive.

The patient leaflet tells people not to take alfuzosin at all if they have certain liver problems, take ketoconazole or itraconazole, take ritonavir, or are allergic to it, and to tell the doctor about low blood pressure, angina or a family history of congenital QT prolongation first. (Source 22)

• Official position, Certainty not rated.
• Size: not applicable.
• Who: men prescribed alfuzosin for benign prostatic hyperplasia.
• How long: before and during treatment.
• Result: no rates given; the leaflet gives a four-item do-not-take list and a five-item tell-your-doctor list.
• Funding: regulator-approved product label (a position, dated 2025)

Limit of this finding: This is the patient-facing version of the label's contraindications. It is a position rather than measured evidence, and the professional label is more specific: the liver limit is moderate or severe hepatic impairment, and the interaction limit is potent CYP3A4 inhibitors as a class.

Do not take UROXATRAL if you: have certain liver problems take antifungal medicines like ketoconazole or itraconazole (Sporanox) take anti-HIV medicines like ritonavir (Norvir, Kaletra) are allergic to alfuzosin hydrochloride or any of the ingredients in UROXATRAL. See the end of this leaflet for a complete list of ingredients in UROXATRAL.

The patient leaflet tells anyone with planned cataract surgery to tell their ophthalmologist that they are taking alfuzosin, or have previously taken any alpha-blocker. (Source 23)

• Official position, Moderate certainty.
• Size: not applicable; a regulator-approved patient instruction, not a study.
• Who: anyone taking or previously treated with alfuzosin who has cataract surgery planned.
• How long: before and during cataract surgery, including after alfuzosin has been stopped.
• Result: no effect size; the instruction exists because intraoperative floppy iris syndrome can be managed if the surgeon knows in advance, and the label says stopping the drug beforehand does not appear to help.
• Funding: regulator-approved label.

Limit of this finding: This is the patient-facing half of the floppy iris warning in section 5.6 (recorded at dailymed-uroxatral-ifis), not separate evidence. The leaflet says "have previously been treated with an alpha-blocker", so the instruction outlives the prescription; the label also states there does not appear to be a benefit in stopping alpha adrenergic antagonist therapy before cataract surgery.

If you have an eye surgery for cataract (clouding of the eye) planned, tell your ophthalmologist that you are using UROXATRAL or have previously been treated with an alpha-blocker.

What the evidence supports

Alfuzosin improved urinary symptom scores more than placebo in men with benign prostatic hyperplasia, by 1.8 points on the International Prostate Symptom Score. (Source 2)

• Systematic review, Moderate certainty.
• Size: 11 trials involving 3,901 men.
• Who: men with symptomatic benign prostatic hyperplasia, mean age 64 years, mean baseline scores indicating moderate disease.
• How long: 4 to 26 weeks.
• Result: mean absolute change from baseline -5.4 points with alfuzosin versus -3.6 points with placebo, a weighted mean difference of 1.8 points from three studies; peak urinary flow improved more than placebo but varied across the eight placebo-controlled studies.
• Funding: not stated in the abstract.

Limit of this finding: The 1.8-point weighted mean difference comes from only three of the eleven trials, while the symptom-score claim is attributed to the whole set; a reader should not read 1.8 points as the pooled estimate from all 3,901 men. On a 0-35 scale a 1.8-point difference is at or below the threshold usually taken as noticeable to a patient. The source changes sign mid-sentence: the two component changes are negative (-5.4 against -3.6 points, where lower is better) but the contrast between them is printed unsigned as "a weighted mean difference of 1.8 points". The direction favours alfuzosin. The symptom-score contrast rests on three studies while the peak-flow sentence beside it refers to eight, so the two outcomes do not share one evidence base.

Alfuzosin (7.5 or 10 mg) improved lower urinary tract symptoms assessed by the International Prostate Symptom Score compared with placebo. The mean absolute change from baseline was -5.4 points for alfuzosin compared with -3.6 points for placebo, a weighted mean difference of 1.8 points (three studies). Alfuzosin increased the peak urinary flow more than did placebo, although the improvement varied across the eight studies.

Alfuzosin was generally well tolerated in the short term, with study withdrawals comparable to placebo. (Source 2)

• Systematic review, Low certainty.
• Size: 11 trials involving 3,901 men.
• Who: men with symptomatic benign prostatic hyperplasia.
• How long: 4 to 26 weeks.
• Result: no pooled withdrawal rate given; the review reports that numbers of study withdrawals were comparable to placebo and controls, and that efficacy and short-term safety were similar across formulations.
• Funding: not stated in the abstract.

Limit of this finding: Tolerability over 4 to 26 weeks says nothing about long-term safety; the review's own conclusion calls for long-term efficacy and safety studies that did not exist.

Alfuzosin had good short-term tolerability, and the numbers of study withdrawals were comparable to those with placebo and controls.

What the evidence does not support

Alpha blockers as a class, including alfuzosin, did not improve overall ureteric stone clearance against placebo. (Source 5)

• Meta-analysis, Low certainty.
• Size: 8 placebo-controlled studies, 2,284 patients.
• Who: people with ureteral calculi receiving tamsulosin, alfuzosin, doxazosin, terazosin, naftopidil or silodosin versus placebo.
• How long: not stated in the abstract.
• Result: overall stone clearance risk ratio 1.05, 95% CI 1.00-1.11; distal stones subgroup risk ratio 1.08, 95% CI 1.02-1.15; dizziness risk ratio 1.37, 95% CI 1.06-1.79; retrograde ejaculation risk ratio 3.10, 95% CI 1.81-5.29.
• Funding: not stated in the abstract.

Limit of this finding: The review calls the overall result not significant while printing a confidence interval of 1.00 to 1.11, whose lower bound sits exactly on no effect, so the overall result is borderline rather than cleanly null. Its own conclusion also names two harms, dizziness and retrograde ejaculation. The outcomes are described as urinary-tract and distal urinary-tract stone clearance but the trials were of ureteric stones, so read "distal" as distal ureteric. The phrase "the combination of MET with alpha-blockers" is circular as printed, because medical expulsive therapy in this review is alpha-blocker therapy.

Generally, α-blockers had no significant effect on the clearance of stones in the urinary tract (risk ratio [RR] = 1.05; 95% confidence interval [CI] = 1.00-1.11). However, subgroup analysis showed that α-blockers were effective in treating distal urinary tract stones (RR = 1.08; 95% CI = 1.02-1.15). With regards to adverse events, our analysis showed that the combination of MET with α-blockers was likely to cause dizziness (RR = 1.37; 95% CI = 1.06-1.79) and retrograde ejaculation (RR = 3.10; 95% CI = 1.81-5.29).

Where the evidence is mixed

Over two years alfuzosin reduced overall clinical progression of benign prostatic hyperplasia but did not reduce acute urinary retention, the trial's primary endpoint. (Source 3)

• Randomized trial, Moderate certainty.
• Size: 1,522 men (759 alfuzosin, 763 placebo)
• Who: men at risk of progression events from lower urinary tract symptoms and benign prostatic hyperplasia.
• How long: 2 years.
• Result: acute urinary retention 2.1% alfuzosin versus 1.8% placebo, P = 0.82; surgery 5.1% versus 6.5%, P = 0.18; symptom deterioration 11.7% versus 16.8%, P = 0.0013, relative risk reduction 30% (10-46)%; overall clinical progression 16.3% versus 22.1%, P < 0.001, an absolute risk reduction of 5.8 percentage points, number needed to treat about 18.
• Funding: not stated in the abstract.

Limit of this finding: Acute urinary retention was the trial's pre-specified primary endpoint and it was not reduced (2.1% against 1.8%, P = 0.82). The composite clinical-progression endpoint and the symptom-deterioration endpoint were both post hoc, so they cannot carry the weight of a primary result, and nothing here shows that alfuzosin prevents retention or changes the course of the disease.

Alfuzosin did not reduce the risk of AUR (alfuzosin 2.1% vs placebo 1.8%, P = 0.82) but tended to reduce the risk of surgery (5.1% vs 6.5%, P = 0.18); the reduction in risk (RR) and 95% confidence interval with alfuzosin was 22 (-18 to 48)%; and significantly reduced the risk of symptom deterioration (11.7% vs 16.8%; P = 0.0013); the RR was 30 (10-46)%.

Alfuzosin increased successful voiding after catheter removal in acute urinary retention, but the six-month surgery endpoint was not significant. (Source 4)

• Randomized trial, Low certainty.
• Size: 360 patients randomised in the first phase; 165 re-randomised in the second phase.
• Who: men with a first episode of acute urinary retention related to benign prostatic hyperplasia.
• How long: 3 days then 6 months.
• Result: successful trial without catheter 146 of 236 (61.9%) with alfuzosin versus 58 of 121 (47.9%) with placebo, P = 0.012, an absolute difference of 14 percentage points and a number needed to treat of about 7; surgery at 6 months 14 of 82 (17.1%) versus 20 of 83 (24.1%); Kaplan-Meier survival improved by 9.6% (P = 0.04) at 1 month, 11.4% (P = 0.04) at 3 months and 8.3% (P = 0.20) at 6 months.
• Funding: not stated in the abstract.

Limit of this finding: The abstract says 360 patients were randomised but the first-phase arms sum to 357 (236 plus 121), and of the 204 men with a successful trial without catheter only 165 appear in the second phase, with no explanation for the other 39. The six-month surgery comparison was P = 0.20, so the trial does not show a six-month benefit; the risk reduction of 29% printed beside it must not be read as established.

Alfuzosin significantly increased the successful TWOC rate (146 of 236, 61.9%) compared with placebo (58 of 121, 47.9%; P = 0.012).

Where the research disagrees

Whether alfuzosin changes the natural course of benign prostatic hyperplasia or only its symptoms

• Roehrborn and colleagues, ALTESS trial, 2006 - the primary endpoint, two-year placebo-controlled randomised trial in 1,522 men; acute urinary retention was the primary endpoint: Alfuzosin did not reduce the risk of AUR (alfuzosin 2.1% vs placebo 1.8%, P = 0.82) (Source 3)
• Roehrborn and colleagues, ALTESS trial, 2006 - the post hoc composite, same trial, post hoc composite endpoint combining symptom deterioration, surgery and retention: The overall clinical progression of BPH was significantly lower with alfuzosin than with placebo (16.3% vs 22.1%, P < 0.001); RR 26 (9-40)%. (Source 3)
• MacDonald and Wilt, systematic review, 2005, systematic review of 11 trials, all 4 to 26 weeks long: The results from short-term studies have indicated that alfuzosin improves lower urinary tract symptoms and urinary flow more than does placebo and is generally well tolerated in men with symptomatic BPH. Long-term efficacy and safety studies in combination with a 5-alpha-reductase inhibitor should be initiated. (Source 2)

Whether alpha blockers help ureteric stones pass

• Yu and colleagues, meta-analysis of placebo-controlled trials, 2021, meta-analysis of 8 placebo-controlled trials, 2,284 patients, six different alpha blockers pooled: Although α-blockers cannot improve the overall ureteral stone clearance rate, these drugs are still effective for the treatment of stones in the distal urinary tract. However, the application of α-blockers is likely to cause dizziness and/or retrograde ejaculation. (Source 5)
• Agrawal and colleagues, three-arm randomised trial, 2009, single randomised trial of 102 patients with lower ureteric stones under 1 cm, in three equal groups of 34: group 1 tamsulosin 0.4 mg daily, group 2 alfuzosin 10 mg daily, group 3 placebo: Stone expulsion was observed in 28 of 34 patients (82.3%) in group 1, 24 of 34 patients (70.5%) in group 2, and 12 of 34 patients (35.2%) in group 3. (Source 24)

How much

• Reference intake: Dosing is set by the prescriber. As a position, the label's recommended dosage is one 10 mg extended-release tablet once daily, taken with food and with the same meal each day, and the tablets are not to be chewed or crushed. (Source 25)
• Upper limit: The leaflet gives the reader no number and no permitted maximum of their own: it says to take UROXATRAL exactly as your doctor prescribes it, to take it after the same meal each day and not on an empty stomach, to swallow the tablet whole without crushing, splitting or chewing it, and, if you take too much, to call your local poison control center or emergency room right away. (Source 23)
• Studied: The three placebo-controlled trials in the label evaluated daily doses of 10 and 15 mg alfuzosin in 1,608 men, of whom 473 received the 10 mg extended-release tablet. (Source 17)
• Studied: The systematic review pooled trials of alfuzosin 7.5 or 10 mg against placebo in men with symptomatic benign prostatic hyperplasia. (Source 2)
• Studied: The two-year progression trial randomised 759 men to alfuzosin 10 mg once daily and 763 to placebo. (Source 3)
• Studied: The acute urinary retention trial gave alfuzosin 10 mg once daily for 3 days, then re-randomised men with a successful trial without catheter to 6 months of alfuzosin 10 mg once daily or placebo. (Source 4)

A common belief, and what the research shows

The belief: Alfuzosin is a prostate drug, so it treats the prostate itself and will stop the condition getting worse.

What the research shows: It relaxes muscle, it does not change the gland. The label describes a muscle-relaxing effect on the bladder and prostate that may lessen symptoms and improve flow: UROXATRAL may help to relax the muscles in the prostate and the bladder which may lessen the symptoms of BPH and improve urine flow. In the two-year trial designed to test whether it prevents the condition's worst event, it did not: Alfuzosin did not reduce the risk of AUR (alfuzosin 2.1% vs placebo 1.8%, P = 0.82). And the symptom benefit itself is modest: a weighted mean difference of 1.8 points on a 35-point score across short trials.

Questions and answers

What is it?

Alfuzosin is a prescription medicine, an alpha blocker, sold as a 10 mg extended-release tablet. Its licensed use is the signs and symptoms of benign prostatic hyperplasia. It is not a blood pressure medicine, even though it lowers blood pressure, and it is not licensed for children. (Source 6)

What does it do in the body?

It blocks alpha1-adrenoreceptors, which are concentrated in the prostate, the bladder base and neck, the prostatic capsule and the prostatic urethra. Blocking them relaxes the smooth muscle there, widening the outflow. In plain terms the label says it may help relax the muscles in the prostate and bladder, which may lessen symptoms and improve urine flow. It does not shrink the prostate. (Source 26)

Is it good or bad for you?

For men with moderate benign prostatic hyperplasia symptoms it does more good than harm in the short term: a 1.8-point symptom-score advantage over placebo and withdrawal rates like placebo. The harms are a roughly doubled rate of dizziness, a small risk of fainting, floppy iris syndrome at cataract surgery, and rare liver injury and priapism. It is clearly the wrong drug for someone on a potent CYP3A4 inhibitor or with moderate to severe liver impairment, where it is contraindicated. (Source 8)

How do you get more of it?

Alfuzosin is a prescription-only synthetic medicine. There is no food, supplement or behaviour that supplies it, and it occurs nowhere in nature. The only thing that changes how much reaches the bloodstream is whether the tablet is taken with a meal: absorption is 50% lower fasting, which is why the label ties it to food and the same meal each day. (Source 9)

If it is harmful, what reduces it?

If alfuzosin is causing harm it is stopped, and there is no antidote. The label's overdose section describes managing the main danger, low blood pressure, by position, intravenous fluids and if needed vasopressors, and notes that because alfuzosin is 82% to 90% protein bound, dialysis may not help. The label also instructs discontinuation if angina appears or worsens. (Source 26)

Why might someone be low in it or missing it?

Alfuzosin is not a nutrient, so nobody is deficient in it; the question translates into who ends up with too little or too much in the blood. Too little comes from taking it on an empty stomach or crushing the extended-release tablet. Too much comes from potent CYP3A4 inhibitors or from liver impairment, and for both reasons those situations are contraindications rather than dose adjustments. (Source 7)

Which whole foods contain it or feed it?

No whole food contains alfuzosin or feeds it. Food matters only as a vehicle: the extent of absorption is half as great fasting, so the label asks for it to be taken with food and with the same meal each day, and for the tablet not to be chewed or crushed. Grapefruit is the food usually raised, and it inhibits the same enzyme the label names, but we found no study measuring grapefruit with alfuzosin. (Source 9)

What happens if you do not have it?

Not taking alfuzosin means the untreated course of benign prostatic hyperplasia. The two-year placebo arm shows what that looked like: symptom deterioration in 16.8% of men, surgery in 6.5%, and acute urinary retention in 1.8%. Alfuzosin changed the first of those and not the last. (Source 3)

How can you test for it?

There is no routine blood test for alfuzosin and no reason to measure it. What is measured instead is the condition and the drug's effects: the International Prostate Symptom Score and peak urinary flow for benefit, blood pressure lying and standing for the main harm, and a prostate-specific antigen test plus examination beforehand because prostate cancer causes the same symptoms and needs different treatment. Symptom scores are patient-reported and so depend on how the question is asked. (Source 26)

References

1. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin hydrochloride) extended-release tablet - section 12.1 Mechanism of Action. 2024. Read the source
2. Urology. Alfuzosin for treatment of lower urinary tract symptoms compatible with benign prostatic hyperplasia: a systematic review of efficacy and adverse effects.. 2005. PMID 16230138, DOI 10.1016/j.urology.2005.05.001. Read the source
3. BJU international. Alfuzosin 10 mg once daily prevents overall clinical progression of benign prostatic hyperplasia but not acute urinary retention: results of a 2-year placebo-controlled study.. 2006. PMID 16536764, DOI 10.1111/j.1464-410X.2006.06110.x. Read the source
4. Urology. Alfuzosin 10 mg once daily in the management of acute urinary retention: results of a double-blind placebo-controlled study.. 2005. PMID 15667868, DOI 10.1016/j.urology.2004.07.042. Read the source
5. Medicine. The efficacy and safety of alpha-adrenergic blockers for medical expulsion therapy in patients with ureteral calculi: A meta-analysis of placebo-controlled trials.. 2021. PMID 34664882, DOI 10.1097/MD.0000000000027272. Read the source
6. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin HCl) extended-release tablets - Highlights of Prescribing Information, INDICATIONS AND USAGE excerpt. 2024. Read the source
7. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin HCl) extended-release tablets - Potent CYP3A4 Inhibitors subsection of section 12.3 Pharmacokinetics. 2024. Read the source
8. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin HCl) extended-release tablets - section 4 CONTRAINDICATIONS. 2024. Read the source
9. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin HCl) extended-release tablets - Effect of Foods subsection of section 12.3 Pharmacokinetics. 2024. Read the source
10. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin HCl) extended-release tablets - section 5.1 Postural Hypotension. 2024. Read the source
11. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin HCl) extended-release tablets - section 7.2 Alpha Adrenergic Antagonists. 2024. Read the source
12. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin HCl) extended-release tablets - section 7.4 PDE5 Inhibitors. 2024. Read the source
13. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin HCl) extended-release tablets - Highlights of Prescribing Information, WARNINGS AND PRECAUTIONS excerpt. 2024. Read the source
14. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin HCl) extended-release tablets - section 5.6 Intraoperative Floppy Iris Syndrome (IFIS). 2024. Read the source
15. Urology. Alfuzosin 10 mg once daily in the management of acute urinary retention: results of a double-blind placebo-controlled study.. 2005. PMID 15667868, DOI 10.1016/j.urology.2004.07.042. Read the source
16. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin hydrochloride) extended-release tablet - PATIENT INFORMATION leaflet from "What are the possible side effects of UROXATRAL?" to the end of the leaflet: the side effects section including the priapism instruction, then storage, general information and the ingredient list. 2024. Read the source
17. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin HCl) extended-release tablets - section 6.1 Clinical Trials Experience, Table 1. 2024. Read the source
18. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin HCl) extended-release tablets - section 6.1 Clinical Trials Experience, orthostasis (Table 2 and blood pressure testing). 2024. Read the source
19. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin HCl) extended-release tablets - section 6.2 Post-Marketing Experience. 2024. Read the source
20. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin hydrochloride) extended-release tablet - section 12.2, Cardiac Electrophysiology: the single-dose thorough-QT study and Table 3 (the rest of the subsection is in dailymed-uroxatral-cardiac-electrophysiology-b). 2024. Read the source
21. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin hydrochloride) extended-release tablet - section 12.2, Cardiac Electrophysiology: the post-marketing QT study of alfuzosin with another QT-prolonging drug. 2024. Read the source
22. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin hydrochloride) extended-release tablet - PATIENT INFORMATION leaflet, "Who should not take UROXATRAL?": the patient-facing do-not-take list, the before-taking disclosure list, and the interacting-medicines list. 2024. Read the source
23. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin hydrochloride) extended-release tablet - PATIENT INFORMATION leaflet, "What you need to know while taking UROXATRAL (alfuzosin HCl) tablets" (the cataract-surgery instruction) and "How do I take UROXATRAL?" (take it after the same meal each day, swallow it whole, and what to do after too much). 2024. Read the source
24. Urology. Prospective randomized trial comparing efficacy of alfuzosin and tamsulosin in management of lower ureteral stones.. 2009. PMID 19193417, DOI 10.1016/j.urology.2008.11.013. Read the source
25. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin hydrochloride) extended-release tablet - section 2 DOSAGE AND ADMINISTRATION. 2024. Read the source
26. DailyMed / US FDA Structured Product Label (Advanz Pharma (US) Corp.). UROXATRAL (alfuzosin hydrochloride) extended-release tablet - FDA-approved PATIENT INFORMATION leaflet, the opening sections "What is the most important information I should know about UROXATRAL?" and "What is UROXATRAL?" (the later sections are in dailymed-uroxatral-patient-information-b and -c). 2024. Read the source