Silodosin Recordati
Highly selective alpha-1A blocker for the treatment of benign prostatic hyperplasia (BPH) in adult men
Silodosin Recordati contains the active substance silodosin and is used to treat the signs and symptoms of benign prostatic hyperplasia (BPH) — an enlarged prostate — in adult men. It belongs to a group of medicines known as highly selective alpha-1A adrenergic blockers, which relax the smooth muscle in the prostate, bladder neck, and prostatic urethra, making it easier to urinate. This page provides comprehensive evidence-based information about silodosin, including its uses, correct dosage, potential side effects, drug interactions, and important warnings.
Quick Facts
Key Takeaways
- Silodosin Recordati is a once-daily, highly selective alpha-1A blocker prescribed for the signs and symptoms of benign prostatic hyperplasia (BPH) in adult men.
- The standard adult dose is one 8 mg capsule once daily, taken with food at approximately the same time each day; a 4 mg dose is recommended for moderate kidney impairment.
- The most common side effect is ejaculation disorder (retrograde or absent ejaculation), which is harmless and reverses within a few days after stopping treatment.
- Silodosin must not be combined with strong CYP3A4 inhibitors (ketoconazole, itraconazole, ritonavir) and is contraindicated in severe hepatic impairment.
- Always inform your eye surgeon before any cataract surgery — silodosin is associated with Intraoperative Floppy Iris Syndrome (IFIS), even after the medication has been discontinued.
What Is Silodosin Recordati and What Is It Used For?
Silodosin Recordati belongs to a group of medicines known as selective alpha-1A adrenergic receptor antagonists. The active substance, silodosin, demonstrates exceptional selectivity for the alpha-1A subtype of the alpha-1 adrenergic receptor — with approximately 583-fold greater affinity for alpha-1A than alpha-1B receptors and 56-fold greater affinity for alpha-1A than alpha-1D receptors. Because alpha-1A receptors are concentrated in the smooth muscle of the prostate gland, the bladder base, the bladder neck, the prostatic capsule, and the prostatic urethra, silodosin is often described as “uroselective.” By blocking these receptors, silodosin relaxes smooth muscle in the lower urinary tract and reduces the obstruction caused by an enlarged prostate.
Benign prostatic hyperplasia (BPH) is one of the most common conditions affecting older men, with prevalence rising steeply after the age of 50. By age 70, more than half of all men have histologically demonstrable BPH, and a substantial proportion experience bothersome lower urinary tract symptoms. The prostate gland sits just below the bladder and surrounds the urethra. As men age, hormonal changes drive a non-cancerous enlargement of the prostate. When this enlargement compresses the urethra, it produces the characteristic urinary symptoms of BPH.
The symptoms of BPH are commonly divided into two groups. Voiding (obstructive) symptoms include hesitancy in starting urination, a weak or interrupted urinary stream, intermittency, straining to urinate, prolonged voiding, sensation of incomplete bladder emptying, and post-void dribbling. Storage (irritative) symptoms include urinary frequency, urgency, nocturia (waking at night to urinate), and urge incontinence. These symptoms can substantially impair quality of life, sleep, and daily functioning, and untreated BPH can lead to complications such as acute urinary retention, recurrent urinary tract infections, bladder stones, and renal impairment.
The European Association of Urology (EAU) and the American Urological Association (AUA) guidelines recognize alpha-1 blockers as first-line pharmacological therapy for moderate to severe BPH symptoms. Silodosin is specifically valued for its high uroselectivity, which translates to rapid symptomatic relief without the cardiovascular side effects (postural hypotension, dizziness) associated with non-selective alpha-blockers. Multiple randomized controlled trials and meta-analyses have shown that silodosin 8 mg once daily significantly improves the International Prostate Symptom Score (IPSS), maximum urinary flow rate (Qmax), and quality-of-life scores compared with placebo. Symptomatic improvement is typically apparent within the first week of treatment, with maximal benefit reached within 2 to 4 weeks.
It is essential to understand what silodosin does and does not do. Silodosin relieves the symptoms of BPH by relaxing the muscular component of urinary obstruction, but it does not shrink the prostate gland itself. Treatments that reduce prostate volume — such as the 5-alpha reductase inhibitors finasteride and dutasteride — act through a different mechanism by blocking the conversion of testosterone to dihydrotestosterone, thereby reducing the hormonal stimulus for prostate growth. These drugs work over months rather than days. In men with significantly enlarged prostates and progressive disease, doctors may prescribe combination therapy with both an alpha-blocker and a 5-alpha reductase inhibitor for more comprehensive long-term management.
Silodosin Recordati is supplied as hard capsules, available in two strengths: 4 mg and 8 mg. The 8 mg capsule is the standard adult dose for patients with normal kidney function, while the 4 mg capsule is reserved for patients with moderate renal impairment. Internationally, silodosin is also marketed under brand names such as Urorec, Silodyx, Rapaflo (in the United States), and Thrupas. Although different brand-name versions may differ slightly in their inactive ingredients, they are pharmacologically equivalent. Always speak to your doctor if your symptoms do not improve within four weeks or if they worsen during treatment.
What Should You Know Before Taking Silodosin Recordati?
Contraindications
There are several situations in which silodosin must not be used. Speak to your doctor immediately if any of the following apply to you before starting treatment:
- Hypersensitivity to silodosin or any excipient: If you have a known allergy to silodosin or to any of the inactive ingredients listed in the composition section, do not take this medication. Symptoms of an allergic reaction may include skin rash, itching, swelling of the face, lips, throat, or tongue, difficulty swallowing, wheezing, or breathing problems.
- Severe hepatic (liver) impairment: Silodosin is extensively metabolized by the liver, primarily by the CYP3A4 enzyme system, with subsequent glucuronidation. Patients with severe liver impairment (Child-Pugh class C) should not take silodosin because impaired liver function can lead to dangerously elevated blood levels and an increased risk of serious side effects.
- Concurrent use of potent CYP3A4 inhibitors: Silodosin must not be taken with strong CYP3A4 inhibitors such as ketoconazole, itraconazole, ritonavir (alone or in combinations such as ombitasvir/paritaprevir or lopinavir/ritonavir), or other HIV protease inhibitors. These drugs can dramatically increase silodosin plasma concentrations, raising the risk of severe hypotension and other adverse effects.
Warnings and Precautions
Speak with your doctor or pharmacist before taking Silodosin Recordati if any of the following situations apply to you:
- Renal (kidney) impairment: No dose adjustment is necessary for patients with mild kidney impairment. For moderate renal impairment, treatment should start with 4 mg once daily and may be increased to 8 mg once daily after one week if well tolerated. Silodosin is not recommended in severe renal impairment due to limited clinical data.
- Mild to moderate hepatic impairment: No dose adjustment is required, but caution is advised because clinical experience in this population is limited. Silodosin is contraindicated in severe hepatic impairment.
- Orthostatic hypotension: Although silodosin causes less postural blood pressure drop than non-selective alpha-blockers, dizziness, lightheadedness, and rarely fainting can still occur, especially at the start of treatment, in elderly patients, when the dose is taken without food, or when combined with other vasodilators or antihypertensive medications.
- Need to exclude prostate cancer: Before starting silodosin, your doctor should confirm that your symptoms are caused by benign prostatic hyperplasia and not by prostate cancer. The two conditions can have similar symptoms but require very different treatments. A digital rectal examination and a prostate-specific antigen (PSA) blood test are typically performed before, and periodically during, alpha-blocker therapy.
If you are scheduled for cataract or glaucoma surgery, tell your eye surgeon (ophthalmologist) before the operation that you are taking, or have ever taken, silodosin. The Intraoperative Floppy Iris Syndrome (IFIS) is a recognized complication of all alpha-1 blockers, particularly the alpha-1A-selective drugs such as silodosin and tamsulosin. IFIS can occur even months or years after the medication has been discontinued. With prior knowledge, your surgeon can plan appropriate techniques and equipment to perform the surgery safely.
In rare cases, silodosin may cause priapism — a prolonged, often painful erection unrelated to sexual activity. If you experience an erection lasting longer than 4 hours, seek emergency medical attention immediately, as untreated priapism can result in permanent erectile dysfunction.
Ejaculation Disorder
One of the most distinctive aspects of silodosin therapy is its very common effect on ejaculation. Approximately 28% to 33% of men taking silodosin experience some form of ejaculation disorder — most commonly retrograde ejaculation (where semen flows backward into the bladder during orgasm) or absent ejaculation (where no semen is released at all). This effect occurs because silodosin’s very high selectivity for alpha-1A receptors in the bladder neck prevents the bladder neck from closing during orgasm. Although this is harmless and fully reversible after stopping the medication (typically within one week), it does affect male fertility while taking silodosin. Men of reproductive age who wish to father a child should discuss alternative therapies with their doctor.
Pregnancy, Breastfeeding, and Fertility
Silodosin Recordati is intended for use in adult men only and is not indicated for women. As described above, silodosin commonly causes ejaculation disorder, which is reversible upon discontinuation. Long-term effects on male fertility have not been established. If you and your partner are planning pregnancy, discuss this with your doctor, as your treatment may need to be temporarily modified.
Driving and Operating Machinery
Silodosin can cause dizziness, orthostatic hypotension, somnolence (drowsiness), and blurred vision, particularly at the beginning of treatment or when the dose is changed. If any of these effects occur, do not drive a vehicle or operate machinery until you know how the medicine affects you. You are personally responsible for assessing whether you are fit to drive or to perform tasks that require alertness. Discuss any concerns with your doctor or pharmacist.
Silodosin Recordati should always be taken together with food, ideally at the same meal each day. Food slows the absorption of silodosin and reduces the peak plasma concentration, which substantially lowers the risk of dizziness and orthostatic hypotension. Taking the capsule on an empty stomach increases the maximum concentration by approximately 30% and is therefore not recommended.
How Does Silodosin Recordati Interact with Other Drugs?
Drug interactions are a critical safety consideration with silodosin. Silodosin is primarily metabolized by the liver enzyme CYP3A4 and to a lesser extent by alcohol dehydrogenase and UDP-glucuronosyltransferase 2B7 (UGT2B7). Drugs that inhibit CYP3A4 can therefore raise silodosin plasma concentrations significantly, while drugs that induce CYP3A4 may reduce its effectiveness. Always inform your doctor or pharmacist about every prescription medicine, over-the-counter medicine, vitamin, herbal supplement, and recreational substance you use, as well as any planned changes to these.
Major Interactions — Do Not Combine
| Drug / Class | Examples | Risk |
|---|---|---|
| Strong CYP3A4 inhibitors | Ketoconazole, itraconazole, ritonavir, lopinavir/ritonavir, ombitasvir/paritaprevir/ritonavir, nirmatrelvir/ritonavir, posaconazole, voriconazole | Marked increase in silodosin plasma levels (up to 3.8-fold AUC); risk of severe hypotension, syncope, and toxicity |
| Other alpha-blockers | Tamsulosin, alfuzosin, doxazosin, terazosin, prazosin, indoramin, phenoxybenzamine | Additive alpha-blockade; substantially increased risk of severe hypotension, syncope, and falls |
| Severe hepatic impairment | Patients with Child-Pugh class C liver disease | Markedly impaired clearance and unpredictable plasma levels; contraindicated |
Moderate Interactions — Use with Caution
| Drug / Class | Examples | Risk |
|---|---|---|
| Moderate CYP3A4 inhibitors | Diltiazem, verapamil, fluconazole, erythromycin, clarithromycin, telithromycin | CYP3A4 inhibition; increased silodosin exposure; monitor for dizziness or hypotension |
| Cyclosporine | Cyclosporine | P-glycoprotein inhibition; raised silodosin plasma concentrations; monitor for adverse effects |
| Antihypertensives | ACE inhibitors, ARBs, calcium channel blockers, beta-blockers, thiazide and loop diuretics | Additive blood pressure-lowering effect; increased risk of dizziness and postural hypotension |
| PDE5 inhibitors | Sildenafil, tadalafil, vardenafil, avanafil | Additive vasodilation; risk of symptomatic hypotension; clinical trials suggest acceptable tolerance with low PDE5 inhibitor doses |
| Nitrates (anti-angina) | Nitroglycerin, isosorbide mononitrate, isosorbide dinitrate | Additive vasodilation; significant blood pressure drop, especially upon standing |
| Strong CYP3A4 inducers | Rifampicin, phenytoin, carbamazepine, St John’s wort (Hypericum perforatum) | Reduced silodosin plasma levels; potential loss of therapeutic effect |
Food, Alcohol, and Lifestyle
Silodosin should always be taken with food because food reduces the peak plasma concentration and slows absorption, which improves tolerability. The composition of the meal does not significantly matter, but consistent timing and consistent meal patterns help maintain steady drug levels. There is no specific food restriction beyond this. Alcohol should be consumed in moderation, particularly in the first weeks of treatment, because alcohol is a vasodilator and may augment the dizziness and orthostatic effects of silodosin. Grapefruit and grapefruit juice, which are moderate CYP3A4 inhibitors, should be consumed cautiously because they may modestly increase silodosin levels.
If you have previously experienced significant blood pressure drops with another alpha-blocker or another vasodilating medication, inform your doctor before starting silodosin. Although silodosin’s alpha-1A selectivity reduces the cardiovascular effect compared with non-selective alpha-blockers, individual susceptibility varies. If you experience dizziness, weakness, sweating, or palpitations after taking silodosin, lie down until the symptoms have completely resolved and contact your doctor, as your medication doses may need to be reviewed.
What Is the Correct Dosage of Silodosin Recordati?
Always take Silodosin Recordati exactly as your doctor has prescribed. Consult your doctor or pharmacist if you are uncertain about any aspect of your treatment. The capsule should be swallowed whole with a glass of water at approximately the same time each day, together with a meal. Do not open, crush, or chew the capsule. Taking silodosin with food is not optional — it significantly reduces the maximum plasma concentration and slows absorption, which lowers the risk of dizziness and orthostatic hypotension during the first hours after dosing.
Adults
Standard Adult Dose
8 mg once daily, taken with food at the same time each day. Symptomatic improvement is typically apparent within 1 to 2 weeks, with maximum benefit reached within 2 to 4 weeks. Continue treatment as long as it remains effective and well tolerated.
Elderly Patients (Over 65 Years)
Elderly Dose
8 mg once daily — no specific dose adjustment is required for patients aged 65 years and older. However, elderly patients are more susceptible to orthostatic hypotension and may be taking multiple medications that lower blood pressure, so additional caution is advised at the start of treatment. Blood pressure monitoring during the first weeks may be appropriate.
Patients with Kidney Problems
Mild Renal Impairment
8 mg once daily — no dose adjustment required.
Moderate Renal Impairment
Start with 4 mg once daily for the first week. If well tolerated, the dose may be increased to 8 mg once daily. Close monitoring for orthostatic hypotension is recommended during the dose-escalation period.
Severe Renal Impairment
Not recommended. Clinical data in patients with severe kidney impairment are limited and elevated drug exposure has been observed. If silodosin is considered necessary, it must only be used under specialist supervision.
Patients with Liver Problems
Mild to Moderate Hepatic Impairment
8 mg once daily — no dose adjustment required, but use with caution due to limited clinical experience.
Severe Hepatic Impairment
Contraindicated. Silodosin must not be used in patients with Child-Pugh class C liver disease because impaired metabolism can lead to dangerously elevated plasma levels.
Children and Adolescents
Silodosin Recordati is not recommended for use in children and adolescents under 18 years of age. The safety and efficacy of silodosin have not been established in this age group. There is also no relevant indication for silodosin in this population, as benign prostatic hyperplasia is essentially a disease of older adult men.
| Patient Group | Dose | Frequency | Notes |
|---|---|---|---|
| Adults (normal renal function) | 8 mg | Once daily | Take with food at same time daily |
| Elderly (>65 years) | 8 mg | Once daily | No adjustment; monitor for hypotension |
| Mild renal impairment | 8 mg | Once daily | No adjustment needed |
| Moderate renal impairment | 4 mg → 8 mg | Once daily | Start at 4 mg; up-titrate after 1 week if tolerated |
| Severe renal impairment | N/A | N/A | Not recommended |
| Mild-moderate hepatic impairment | 8 mg | Once daily | No adjustment; use with caution |
| Severe hepatic impairment | N/A | N/A | Contraindicated |
| Children & adolescents (<18 years) | N/A | N/A | Not recommended; no relevant indication |
Missed Dose
If you forget to take your daily dose of Silodosin Recordati, take it with your next meal as soon as you remember on the same day. If it is already close to the time of your next scheduled dose, simply skip the missed dose and resume your normal schedule the following day. Do not take a double dose to make up for the one you missed. Taking two capsules at once increases the risk of side effects, particularly dizziness and a drop in blood pressure. If you miss several consecutive doses, contact your doctor for advice before resuming treatment, as you may need to restart at a lower dose.
Overdose
If you take more silodosin than prescribed, or if a child accidentally swallows the medicine, contact your local poison control center or emergency services immediately. The most likely consequences of overdose are pronounced hypotension and reflex tachycardia. Lie down with your legs raised to support blood pressure and minimize the risk of fainting until medical help arrives. Do not attempt to drive yourself to the hospital. Bring the medicine packaging with you so the medical team knows exactly what was taken. There is no specific antidote for silodosin overdose; treatment is supportive (intravenous fluids, vasopressors if required) and dialysis is not effective due to high plasma protein binding.
Stopping Treatment
Continue taking Silodosin Recordati for as long as your doctor prescribes, even if your symptoms improve significantly. Symptoms of BPH typically return when alpha-blocker therapy is stopped, because the underlying prostatic enlargement remains. There is no need to taper the dose — silodosin can be stopped abruptly without rebound hypertension because it is not a centrally acting antihypertensive. If you experience troublesome side effects or have any questions about your treatment, discuss them with your doctor or pharmacist before deciding to stop the medicine.
What Are the Side Effects of Silodosin Recordati?
Like all medicines, Silodosin Recordati can cause side effects, although not everyone experiences them. Side effects are more common at the start of treatment as your body adjusts to the medication. The following list groups side effects by frequency, based on data from clinical trials and post-marketing surveillance reported in the European Medicines Agency Summary of Product Characteristics.
- Severe allergic reaction (anaphylaxis or angioedema): swelling of the face, eyelids, lips, mouth, or tongue, hives, difficulty breathing or swallowing, rapid pulse, faintness, or collapse.
- Priapism: a persistent, painful erection lasting more than 4 hours and unrelated to sexual activity. This is a medical emergency.
- Syncope (fainting): sudden loss of consciousness, particularly when standing up or after the first dose.
- Severe rash with blistering, fever, or mouth ulcers: may indicate a serious skin reaction such as Stevens-Johnson syndrome.
Very Common
May affect more than 1 in 10 people
- Ejaculation disorder — retrograde ejaculation (semen flows back into the bladder during orgasm) or absent ejaculation. Reversible within days after stopping treatment.
Common
May affect up to 1 in 10 people
- Dizziness
- Orthostatic hypotension (drop in blood pressure when standing up)
- Nasal congestion (stuffy or runny nose)
- Diarrhea
Uncommon
May affect up to 1 in 100 people
- Reduced libido (decreased sexual desire)
- Nausea
- Dry mouth
- Erectile dysfunction
- Tachycardia (fast heartbeat)
- Skin rash
- Itching (pruritus)
- Hives (urticaria)
- Drug eruption
- Headache
Rare
May affect up to 1 in 1,000 people
- Syncope (fainting), loss of consciousness
- Palpitations
- Liver function test abnormalities (raised ALT, AST, bilirubin)
Frequency Not Known
Cannot be estimated from available data
- Severe allergic reaction (anaphylactoid reaction, angioedema, swelling of face or throat)
- Priapism (prolonged, painful erection unrelated to sexual activity)
- Intraoperative Floppy Iris Syndrome (IFIS) during cataract surgery
- Yellowing of skin or eyes (jaundice) related to liver injury
Why Does Silodosin Cause Ejaculation Disorder?
The high frequency of ejaculation disorder with silodosin is a direct consequence of its very high selectivity for the alpha-1A adrenergic receptor subtype. During the male orgasm, contraction of the bladder neck (mediated by alpha-1A receptors) prevents semen from flowing backward into the bladder, ensuring normal forward (antegrade) ejaculation. By blocking these receptors, silodosin prevents bladder neck closure, so semen either flows backward into the bladder (retrograde ejaculation) or is not expelled at all (anejaculation). Although this can be alarming the first time it is experienced, it is not painful, not harmful, and does not require medical treatment. Sexual sensation and orgasm are unaffected, and the effect resolves completely within a few days of stopping silodosin. Men who wish to retain natural fertility should discuss with their doctor whether an alternative alpha-blocker with lower alpha-1A selectivity (such as alfuzosin) may be more suitable.
Cataract Surgery and Intraoperative Floppy Iris Syndrome
If you are scheduled for cataract surgery (removal of a cloudy lens in the eye), it is essential to inform your eye specialist (ophthalmologist) before the procedure that you are taking, or have ever taken, silodosin. Silodosin and other alpha-1A blockers are associated with Intraoperative Floppy Iris Syndrome (IFIS), in which the iris (the colored part of the eye) becomes flaccid during surgery, the pupil progressively constricts despite preoperative dilation, and the iris may prolapse through surgical incisions. IFIS can complicate cataract surgery and increase the risk of intraoperative complications. Critically, IFIS may occur even months or years after silodosin has been stopped, so simply discontinuing the medicine in the days before surgery does not eliminate the risk. With prior knowledge, however, your surgeon can use specialized techniques such as iris hooks, pupil expansion rings, intracameral phenylephrine, or modified surgical technique to perform the operation safely.
Reporting Side Effects
If you experience any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed on this page. You can also report side effects directly to your national medicines regulatory authority. In the United Kingdom, report to the Medicines and Healthcare products Regulatory Agency (MHRA) via the Yellow Card Scheme. In the United States, report to the FDA MedWatch program. In the European Union, report to your national authority via the European database EudraVigilance. By reporting side effects, you help provide valuable information about the long-term safety of medicines.
How Should You Store Silodosin Recordati?
Proper storage is important to maintain the quality, potency, and safety of any medication. Silodosin Recordati should be stored according to the following recommendations.
- Temperature: Store below 30°C. Avoid storing the medication near sources of heat such as radiators, ovens, or in direct sunlight. Do not refrigerate or freeze.
- Humidity: Store in the original packaging (blister pack) to protect the capsules from moisture. The bathroom medicine cabinet is generally a poor storage location because of high humidity from showers and baths. A bedroom drawer, kitchen cabinet (away from the stove), or living room cupboard is preferable.
- Keep out of sight and reach of children. Store the medication in a secure location, ideally in a child-resistant container or locked cabinet, where children cannot access it. Even small doses can be dangerous to children.
- Check the expiry date printed on the blister pack and outer carton before each use. The expiry date refers to the last day of the stated month. Do not take the medicine after this date, as the active ingredient may have degraded and the safety profile may have changed.
- Visual inspection: Do not use any capsule that appears damaged, discolored, or unusual. If the blister foil is punctured or torn, the capsule may have been exposed to moisture and should not be used.
- Proper disposal: Do not dispose of unused or expired medicines by flushing them down the toilet or throwing them in household waste. Return unused medicines to your local pharmacy for safe disposal. This protects the environment and prevents accidental ingestion by others. Many countries operate medicine take-back programs through community pharmacies.
What Does Silodosin Recordati Contain?
Understanding the full composition of your medicine can be helpful, especially if you have known allergies or intolerances to specific excipients (inactive ingredients). The exact composition may vary slightly between manufacturing batches and pack types, so always refer to the patient information leaflet supplied with your specific pack.
Active Ingredient
Each hard capsule contains either 4 mg or 8 mg of silodosin, the therapeutically active substance responsible for the medication’s pharmacological effects. Silodosin is chemically described as 1-(3-hydroxypropyl)-5-[(2R)-2-({2-[2-(2,2,2-trifluoroethoxy)phenoxy]ethyl}amino)propyl]-2,3-dihydro-1H-indole-7-carboxamide.
Inactive Ingredients (Excipients)
Capsule contents: pregelatinized maize starch, mannitol (E421), magnesium stearate, sodium lauryl sulfate.
Capsule shell: gelatin and titanium dioxide (E171). The 4 mg capsule shell additionally contains yellow iron oxide (E172) to give it its characteristic color.
Allergy and Intolerance Notes
The capsule shell contains gelatin, which is derived from animal sources. Patients following strict vegetarian, vegan, or certain religious dietary practices may wish to discuss this with their doctor or pharmacist. The capsules contain mannitol but in quantities unlikely to cause symptoms in patients with mannitol intolerance. Sodium content per capsule is essentially negligible (less than 1 mmol of sodium per dose), making the medication essentially “sodium-free.”
Appearance and Pack Sizes
Silodosin Recordati 4 mg hard capsules are yellow, opaque capsules. The 8 mg hard capsules are white, opaque capsules. Both strengths are typically supplied in PVC/PVDC/aluminium blister packs of 5, 10, 20, 30, 50, 90, or 100 capsules. Not all pack sizes may be marketed in every country.
Frequently Asked Questions About Silodosin Recordati
Silodosin Recordati is used to treat the signs and symptoms of benign prostatic hyperplasia (BPH) in adult men. BPH is a non-cancerous enlargement of the prostate gland that develops with age and presses on the urethra, causing urinary symptoms. Silodosin belongs to a class of medicines called selective alpha-1A blockers, which relax the smooth muscle in the prostate, bladder neck, and prostatic urethra. This reduces urethral constriction and makes it easier to start urinating, improves urinary flow, and reduces the need to wake at night to pass urine. Silodosin does not reduce the size of the prostate but provides rapid symptomatic relief, typically within the first week of treatment.
Take one capsule once daily at approximately the same time each day, together with food. Swallow the capsule whole with a glass of water. Do not open, crush, or chew the capsule. Taking silodosin with food is essential because food slows the absorption and reduces the maximum blood concentration, which significantly lowers the risk of dizziness and orthostatic hypotension. The standard adult dose is 8 mg once daily; a 4 mg dose is recommended for patients with moderate kidney impairment. Continue treatment for as long as your doctor prescribes, even if symptoms improve, because BPH symptoms typically return when treatment stops.
Silodosin very commonly causes a side effect called retrograde or absent ejaculation, affecting approximately one in three men. This happens because silodosin selectively blocks alpha-1A receptors in the bladder neck. During orgasm, these receptors normally cause the bladder neck to close, directing semen forward through the urethra. When silodosin blocks these receptors, the bladder neck stays open, so semen flows backward into the bladder (retrograde ejaculation) or is not released at all (anejaculation). Sexual sensation, arousal, and orgasm itself are not affected. The effect is harmless and reversible — it resolves within a few days of stopping treatment. However, it does affect male fertility while taking the medication, so men trying to conceive should discuss alternatives with their doctor.
Silodosin can cause orthostatic hypotension — a drop in blood pressure when standing up — but the risk is lower than with non-selective alpha-blockers because silodosin is highly selective for alpha-1A receptors in the prostate rather than alpha-1B receptors in blood vessels. Dizziness affects approximately 1 in 30 to 1 in 50 patients overall. The risk is highest at the start of treatment, in elderly patients, when the dose is taken on an empty stomach, and when combined with other antihypertensive medications, nitrates, or PDE5 inhibitors such as sildenafil or tadalafil. To minimize this risk, always take silodosin with food, rise slowly from sitting or lying positions during the first weeks of treatment, and report any persistent dizziness to your doctor.
Silodosin must not be combined with potent CYP3A4 inhibitors such as ketoconazole, itraconazole, ritonavir, and other HIV protease inhibitors, which can dramatically increase silodosin blood levels. It should not be taken together with another alpha-blocker (tamsulosin, alfuzosin, doxazosin, terazosin, or prazosin), as this doubles the risk of hypotension. Caution is needed with cyclosporine (a P-glycoprotein inhibitor), moderate CYP3A4 inhibitors such as clarithromycin, diltiazem, or verapamil, blood pressure-lowering medications, nitrates for chest pain, and PDE5 inhibitors for erectile dysfunction. CYP3A4 inducers such as rifampicin, carbamazepine, phenytoin, and St John’s wort can reduce silodosin’s effectiveness. Always provide your doctor with a complete list of all medications, supplements, and herbal products you are taking.
Yes — silodosin can cause Intraoperative Floppy Iris Syndrome (IFIS) during cataract surgery, even if the medication has been stopped weeks, months, or years earlier. IFIS occurs when the iris becomes flaccid during the operation, the pupil progressively constricts despite preoperative dilation, and the iris may prolapse through surgical incisions. Always tell your eye surgeon (ophthalmologist) before any planned cataract operation that you are taking or have ever taken silodosin or any other alpha-blocker (such as tamsulosin, alfuzosin, doxazosin, or terazosin). With this information, the surgeon can use specialized techniques such as iris hooks, pupil expansion rings, intracameral phenylephrine, or modified surgical methods to perform the operation safely. There is no benefit to stopping silodosin in the days before surgery, because the IFIS risk persists long after discontinuation.
Most men notice improvement in urinary symptoms within the first week of starting silodosin, with peak benefit reached after 2 to 4 weeks of treatment. Improvements include a stronger and more continuous urinary stream, easier initiation of urination, reduced sense of incomplete emptying, and fewer nighttime trips to the toilet. If you do not notice any improvement after 4 weeks of regular use, contact your doctor for review — you may need an alternative therapy or further investigation. Silodosin treats symptoms but not the underlying enlargement, so symptoms typically return within days if treatment stops. For long-term disease modification, your doctor may add a 5-alpha reductase inhibitor (finasteride or dutasteride) to shrink the prostate gradually over several months.
Yes, silodosin 8 mg once daily is generally well tolerated in elderly patients, and BPH is most common in this age group. No dose adjustment based on age alone is required. However, elderly patients may have reduced kidney function, take multiple medications that lower blood pressure, and be more prone to falls, so additional caution is advised. Your doctor may check kidney function before starting silodosin and may recommend the lower 4 mg starting dose if your creatinine clearance suggests moderate renal impairment. During the first weeks of treatment, take care when standing up from sitting or lying positions to minimize the risk of dizziness or falls, and report any persistent dizziness, fainting, or unusual symptoms to your healthcare provider.
References
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- Gravas S, Cornu JN, Gacci M, et al. EAU Guidelines on Management of Non-Neurogenic Male Lower Urinary Tract Symptoms (LUTS), incl. Benign Prostatic Obstruction (BPO). European Association of Urology; 2024. uroweb.org/guidelines.
- Sanford M, Scott LJ. Silodosin: a review of its use in adults with lower urinary tract symptoms suggestive of benign prostatic hyperplasia. Drugs Aging. 2011;28(11):883–901. doi:10.2165/11208200-000000000-00000.
- Chapple CR, Montorsi F, Bäckman A, et al. Silodosin therapy for lower urinary tract symptoms in men with suspected benign prostatic hyperplasia: results of an international, randomized, double-blind, placebo- and active-controlled clinical trial. Eur Urol. 2011;59(3):342–352. doi:10.1016/j.eururo.2010.10.046.
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