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Alpha-1 Blocker Pregnancy: UK SPC §4.6, verbatim and in full: 'This section is not applicable given the therapeutic indications.' (Alfuzosin is used for benign prostatic hyperplasia.) US §8.1 states: 'Alfuzosin hydrochloride extended-release tablets are not indicated for use in women. There are no adequate data on the developmental risk associated with the use of alfuzosin hydrochloride extended-release tablets in pregnant women. Based on findings from animal studies alfuzosin administered during the period of organogenesis was not teratogenic, embryotoxic or fetotoxic at up to 1200 times the MRHD of 10 mg via AUC in rats and 3 times in rabbits, via body surface area.'

Alfuzosin

Brand names: Xatral

Alfuzosin is an alpha-1 adrenoceptor antagonist used to relieve the lower urinary tract symptoms associated with benign prostatic hyperplasia.

Adult dose

Dose: Immediate-release 2.5 mg tablets (UK SPC): 2.5 mg (one tablet) three times daily, increased according to clinical response. Extended-release 10 mg tablet (US label — no UK SPC for this formulation in the bundle): 10 mg once daily.
Route: Oral. UK SPC §4.2: 'Alfuzosin HCl 2.5 mg film-coated tablets should be swallowed whole. The first dose should be given just before bedtime.' US label §2 for the extended-release tablet: 'The extent of absorption of alfuzosin is 50% lower under fasting conditions. Therefore, alfuzosin hydrochloride extended-release tablets should be taken with food and with the same meal each day. The tablets should not be chewed or crushed.'
Frequency: Three times daily for the immediate-release 2.5 mg tablet (UK SPC), the first dose just before bedtime; once daily for the 10 mg extended-release tablet (US label), with food and with the same meal each day.
Max: Maximum 10 mg per day (4 tablets of 2.5 mg) — UK SPC §4.2, verbatim: 'The dose may be increased to a maximum of 4 tablets (10 mg) per day depending on the clinical response.' The US extended-release label's recommended dosage is likewise 10 mg once daily, so 10 mg per day is the ceiling on both labels in this bundle.
VERBATIM UK SPC §4.2 (Adults) — 'The usual dose is one tablet three times daily. The dose may be increased to a maximum of 4 tablets (10 mg) per day depending on the clinical response.' The dose is expressed as a tablet count; the strength is pinned by the product name (Alfuzosin HCl 2.5 mg film-coated tablets) and confirmed internally by the maximum line (4 tablets = 10 mg). ELDERLY AND TREATED HYPERTENSIVE PATIENTS (§4.2): 'As a routine precaution when prescribing alfuzosin to elderly patients (aged over 65 years) and the treated hypertensive patient, the initial dose should be 1 tablet in the morning and 1 tablet in the evening.' VERBATIM US §2 (extended-release): 'The recommended dosage is one 10 mg alfuzosin hydrochloride extended-release tablet once daily.' FORMULATION WARNING: the two regimens are not interchangeable tablet-for-tablet — 2.5 mg three times daily is the immediate-release schedule, 10 mg once daily is the extended-release schedule; both reach the same 10 mg daily ceiling. Confirm which formulation is being prescribed, and fetch the UK SPC for the 10 mg modified-release product before relying on a UK once-daily figure. INDICATION: neither fetched section states §4.1 explicitly, but the BPH setting is confirmed by UK §4.4 ('The patient should be examined prior to treatment with alfuzosin to exclude other conditions, which may cause the same symptoms as benign prostatic hyperplasia. A digital rectal examination should be performed prior to treatment and regularly during treatment. A prostate specific antigen (PSA) test should also be carried out if required.') and by US §5.5 ('Prostate carcinoma should be ruled out prior to treatment') and §8.1 ('not indicated for use in women'). CYP3A4 (§4.4): 'Concomitant use of alfuzosin and potent CYP3A4 inhibitors (such as itraconazole, ketoconazole, protease inhibitors, clarithromycin, telithromycin and nefazodone) should be avoided… Alfuzosin should not be used concomitantly with CYP3A4 inhibitors that are known to increase the QTc interval (e.g. itraconazole and clarithromycin) and a temporary interruption of alfuzosin treatment is recommended if treatment with such medicinal products is initiated.' The US label makes potent CYP3A4 inhibitors an outright contraindication. ANGINA (§4.4): 'In coronary patients, the specific treatment for coronary insufficiency should be continued. If angina pectoris reappears or worsens, alfuzosin should be discontinued.' CATARACT SURGERY (§4.4): intraoperative floppy iris syndrome has been observed with alpha-1 blockers — 'the possibility of a class effect cannot be excluded'. PAEDIATRIC (§4.2, verbatim): 'Efficacy of alfuzosin has not been demonstrated in children aged 2 to 16 years (see section 5.1). Therefore, alfuzosin is not indicated for use in paediatric population.' US §8.4 agrees — efficacy was not demonstrated in a randomised placebo-controlled trial in 172 patients aged 2 to 16 years with elevated detrusor leak point pressure of neurologic origin, and 'Alfuzosin hydrochloride was not studied in patients below the age of 2' — hence paedDose is null.

Dose adjustments

Renal

UK SPC §4.2, verbatim: 'In patients with renal insufficiency, as a precaution, it is recommended that the dosing be started at Alfuzosin HCl 2.5mg twice daily adjusted according to clinical response.' No creatinine clearance or eGFR threshold accompanies that statement in the fetched UK text. US label §5.2/§8.6: 'Use with caution in patients with severe renal impairment (creatinine clearance <30 mL/min)' — the US extended-release label gives no reduced dosage figure.

Hepatic

UK SPC §4.2, verbatim: 'In patients with mild to moderate hepatic insufficiency, it is recommended that therapy should commence with a single dose of Alfuzosin HCl 2.5 mg Tablets/day to be increased to Alfuzosin HCl 2.5 mg Tablets twice daily according to clinical response. Alfuzosin HCl 2.5 mg tablets are contraindicated in patients with severe hepatic insufficiency (see section 4.3).' The US extended-release label is more restrictive: §4 contraindicates it 'in patients with moderate or severe hepatic impairment (Childs-Pugh categories B and C), since alfuzosin blood levels are increased in these patients', and §5.3 advises caution in mild hepatic impairment.

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

The recommended dosage is one 10 mg alfuzosin hydrochloride extended-release tablet once daily. The extent of absorption of alfuzosin is 50% lower under fasting conditions. Therefore, alfuzosin hydrochloride extended-release tablets should be taken with food and with the same meal each day. The tablets should not be chewed or crushed. 10 mg once daily with food and with the same meal each day. ( 2 ) Tablets should not be chewed or crushed ( 2 , 12.3 )

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2025-04-02. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Contraindications

  • Hypersensitivity to alfuzosin, to another quinazoline (e.g. terazosin, doxazosin) or to any of the excipients (UK SPC §4.3; US §4 lists known hypersensitivity such as urticaria and angioedema)
  • History of orthostatic hypotension (UK SPC §4.3)
  • Combination with other alpha-1 blockers and/or dopamine receptor agonists (UK SPC §4.3; US §5.4/§7.2 states it 'should not be used in combination with other alpha adrenergic antagonists')
  • Severe hepatic insufficiency (UK SPC §4.3); the US label extends this to moderate or severe hepatic impairment, Child-Pugh B and C (US §4)
  • Co-administration with potent CYP3A4 inhibitors such as ketoconazole, itraconazole or ritonavir — an outright contraindication on the US label (§4, §7.1); the UK SPC §4.4 states such combinations 'should be avoided' rather than listing them in §4.3

Side effects

  • Nervous system: faintness/dizziness, headache, vertigo; also syncope and drowsiness (UK §4.8)
  • Vascular: postural hypotension, flushing (UK §4.8); §4.4 notes postural hypotension 'with or without symptom (dizziness, fatigue, sweating) within a few hours following administration' and a pronounced drop in blood pressure in patients with pre-existing risk factors
  • Cardiac: tachycardia, palpitations; angina pectoris in patients with pre-existing coronary artery disease; atrial fibrillation (UK §4.8)
  • Gastrointestinal: nausea, abdominal pain, diarrhoea, dry mouth, vomiting (UK §4.8)
  • Eye: abnormal vision; intraoperative floppy iris syndrome during cataract surgery (UK §4.8/§4.4; US §5.6 notes it 'may require modifications to the surgical technique')
  • Hepatobiliary: hepatotoxicity, hepatocellular injury, cholestatic liver disease (UK §4.8)
  • Blood: neutropenia, thrombocytopenia (UK §4.8)
  • Skin: rash, pruritus, urticaria, angioedema (UK §4.8)
  • Reproductive: priapism (UK §4.8)
  • Respiratory: rhinitis (UK §4.8). General: asthenia, malaise, oedema, chest pain (UK §4.8)
  • US §6: 'Most common adverse reactions in clinical studies (incidence ≥2% and at a higher incidence than placebo): dizziness, upper respiratory tract infection, headache, fatigue' — 4% of patients taking the 10 mg extended-release tablet withdrew because of adverse reactions, versus 3% on placebo
  • NOTE ON FREQUENCIES: the UK §4.8 table's Common / Uncommon / Very rare / Not known columns could not be reliably aligned to individual reactions in the fetched text, so no frequency category is asserted for any UK reaction above — read the SPC table directly if frequency matters

Monitoring

  • Blood pressure at the start of treatment — UK §4.4: 'Blood pressure should be monitored at the start of treatment. A reduction in blood pressure may arise in individual cases'
  • Warn the patient about postural hypotension and syncope; UK §4.4: 'In cases of orthostatic hypotension the patient should lie or sit down until the symptoms have disappeared'
  • Prostate assessment before and during treatment — UK §4.4: 'A digital rectal examination should be performed prior to treatment and regularly during treatment. A prostate specific antigen (PSA) test should also be carried out if required.' US §5.5: 'Prostate carcinoma should be ruled out prior to treatment'
  • QTc — UK §4.4: 'Patients with congenital QTc prolongation, with a known history of acquired QTc prolongation or who are taking drugs known to increase the QTc interval should be evaluated before and during the administration of alfuzosin'
  • Angina — UK §4.4: 'If angina pectoris reappears or worsens, alfuzosin should be discontinued'; US §5.8 says the same
  • Before cataract surgery: tell the ophthalmologist the patient is taking, or has taken, an alpha-1 blocker (intraoperative floppy iris syndrome, UK §4.4/§4.8, US §5.6)
  • Extra care in patients on antihypertensives or nitrates, and in those who have had a pronounced hypotensive response to another alpha-1 blocker (UK §4.4; US §5.1, §7.3); caution also with PDE5 inhibitors, which 'can potentially cause symptomatic hypotension' (US §7.4)

Clinical monograph

How it works

It selectively blocks alpha-1 adrenoceptors in the smooth muscle of the prostate, prostatic capsule and bladder neck, reducing urethral tone and outflow resistance to improve urinary flow and symptoms.

Prescribing in practice

  • Patients due to have cataract or other eye surgery must tell the ophthalmologist they take, or have taken, this medicine, as it is associated with intraoperative floppy iris syndrome.
  • It can cause postural hypotension and a first-dose effect, with dizziness, light-headedness and rarely syncope, particularly on initiation or dose increase.
  • Use with caution in patients with cardiovascular disease and those taking other blood-pressure-lowering or QT-affecting drugs; consult the SPC for detail.

Monitoring

Monitor blood pressure, particularly after the first dose and on dose changes, and review for dizziness or postural symptoms. Ensure planned ophthalmic surgery is flagged so the surgeon can anticipate floppy iris syndrome.

Counselling the patient

  • If you are going to have eye surgery for cataracts, tell the eye surgeon you take this medicine, even if you stopped it some time ago.
  • The first dose may make you feel dizzy or faint — take it as advised, ideally at bedtime, and get up slowly from sitting or lying.
  • Take care when driving or using machinery until you know how it affects you.

Evidence & guidelines

An established alpha-blocker recommended in UK guidance (NICE) for moderate-to-severe lower urinary tract symptoms due to benign prostatic hyperplasia.

Reference: NICE NG97; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Related

Curated clinical cross-links plus same-class fallbacks.

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