Does silodosin help with erectile dysfunction? This is a common question among men prescribed this medication for urinary symptoms. Silodosin is an alpha-blocker licensed in the UK to treat lower urinary tract symptoms associated with benign prostatic hyperplasia (BPH), not erectile dysfunction. In fact, one of its most frequently reported side effects is abnormal ejaculation, affecting more than 1 in 10 users. Understanding how silodosin works, its impact on sexual function, and the appropriate treatments for erectile dysfunction is essential for men managing both prostate and sexual health concerns.

What Is Silodosin and How Does It Work?

Silodosin is a selective alpha-1A adrenoceptor antagonist (alpha-blocker) licensed in the UK for treating the lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH) in adult men. Unlike some other alpha-blockers, silodosin demonstrates high selectivity for the alpha-1A receptor subtype, which is predominantly found in the prostate gland, bladder neck, and prostatic urethra.

The medication works by relaxing the smooth muscle in these areas, thereby reducing urinary obstruction and improving urine flow. This mechanism helps alleviate bothersome symptoms such as hesitancy, weak stream, frequency, urgency, and nocturia. The typical dose is 8 mg once daily, taken with food. For patients with moderate renal impairment, the starting dose is 4 mg once daily, which may be increased to 8 mg after one week if well tolerated. Silodosin is contraindicated in severe renal impairment and severe hepatic impairment, and should be used with caution in mild to moderate hepatic impairment.

It is important to clarify that silodosin is not licensed to treat erectile dysfunction (ED). In fact, one of the most commonly reported adverse effects of silodosin is abnormal ejaculation, including retrograde ejaculation (where semen enters the bladder rather than being expelled through the urethra) or reduced ejaculatory volume. This occurs in a significant proportion of men taking the medication—classified as a 'very common' side effect (affecting more than 1 in 10 users) in the Summary of Product Characteristics.

Other important safety considerations include:

• Risk of orthostatic hypotension (dizziness when standing up), particularly when starting treatment

• Contraindication with strong CYP3A4 inhibitors (e.g., ketoconazole, ritonavir)

• Risk of intraoperative floppy iris syndrome (IFIS) during cataract surgery; ophthalmologists should be informed of current or previous silodosin use

Whilst silodosin effectively manages urinary symptoms, there is no robust evidence suggesting it improves erectile function. Men experiencing both BPH and ED require separate assessment and management for each condition, as the underlying causes and treatment approaches differ substantially.

Why Erectile Dysfunction May Occur with Prostate Medications

Erectile dysfunction can be associated with both benign prostatic hyperplasia itself and the medications used to treat it, though the relationship is complex and multifactorial. Men with BPH are often older and may have comorbidities such as diabetes, cardiovascular disease, or hypertension—all independent risk factors for ED. The psychological impact of bothersome urinary symptoms can also contribute to sexual difficulties.

Alpha-blockers and sexual function: Different alpha-blockers have varying effects on sexual function. Whilst silodosin's high selectivity for alpha-1A receptors may reduce certain systemic side effects, it paradoxically increases the risk of ejaculatory dysfunction. Other alpha-blockers such as tamsulosin and alfuzosin also carry this risk, though typically at lower rates. Some studies suggest that improvements in erectile function sometimes reported with alpha-blockers may primarily reflect better quality of life from improved urinary symptoms rather than direct effects on erectile tissue, but evidence remains inconsistent.

5-alpha reductase inhibitors: Medications such as finasteride and dutasteride, which are also used for BPH, work by reducing prostate size through hormonal mechanisms. These drugs are associated with sexual side effects, including reduced libido, erectile dysfunction, and ejaculatory disorders. The MHRA has issued safety updates highlighting that finasteride can cause psychiatric adverse reactions and sexual dysfunction that may persist after treatment discontinuation. Patients should be informed of these risks and advised to report any changes in mood or sexual function.

The distinction is crucial: Silodosin does not cause ED through the same mechanisms as 5-alpha reductase inhibitors, but it can significantly affect ejaculation. Men concerned about sexual side effects should discuss the full range of BPH treatment options with their GP or urologist, as individual risk profiles and priorities vary considerably.

If you experience side effects from any medication, you can report them through the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk or via the Yellow Card app).

Treatment Options for Erectile Dysfunction

When erectile dysfunction occurs alongside BPH, a comprehensive assessment is essential to identify contributing factors and guide appropriate management. NICE guidance emphasises that ED assessment should include evaluation of cardiovascular risk factors, psychological wellbeing, hormonal status, and medication review.

Phosphodiesterase type 5 (PDE5) inhibitors remain the first-line pharmacological treatment for ED in the UK. These include:

• Sildenafil (Viagra) – typically 50 mg, taken approximately one hour before sexual activity

• Tadalafil (Cialis) – available as 10-20 mg on-demand doses or 5 mg daily for regular use

• Vardenafil (Levitra) – 10 mg as needed

• Avanafil (Spedra) – 100 mg, with onset from approximately 15-30 minutes

Tadalafil 5 mg daily has the additional benefit of being licensed for both ED and LUTS associated with BPH, making it a potentially useful option for men with both conditions. This dual indication means some men may be able to simplify their medication regimen.

Important safety considerations: PDE5 inhibitors are contraindicated in men taking nitrates (for angina) due to the risk of severe hypotension. They should also be avoided in unstable cardiovascular disease. When using PDE5 inhibitors with alpha-blockers:

• Ensure you are stable on alpha-blocker therapy before starting a PDE5 inhibitor

• For sildenafil, start with the lowest dose (25 mg) and take at least 4 hours apart from alpha-blocker doses

• The combination of tadalafil with alpha-blockers for BPH treatment is generally not recommended unless under specialist supervision

Your GP or specialist will assess your suitability based on your cardiovascular health and current medications.

Alternative and adjunctive treatments include:

• Vacuum erection devices – mechanical aids that draw blood into the penis

• Intracavernosal injections (alprostadil) – for men who cannot use or do not respond to oral medications

• Psychological therapy – particularly cognitive behavioural therapy (CBT) for performance anxiety or relationship issues

• Lifestyle modifications – weight loss, exercise, smoking cessation, and alcohol reduction

• Testosterone replacement – only when hypogonadism is confirmed through blood tests

For men whose ED is primarily related to ejaculatory dysfunction from silodosin rather than true erectile problems, switching to an alternative BPH medication with a different side effect profile may be appropriate. This decision should be made collaboratively with your healthcare provider, weighing the benefits of improved urinary symptoms against sexual side effects.

When to Speak with Your GP About Sexual Side Effects

Sexual side effects from medications can significantly impact quality of life and relationships, yet many men feel uncomfortable discussing these issues. It is important to recognise that your GP is accustomed to these conversations and can offer practical solutions.

You should arrange an appointment if you experience:

• New or worsening erectile difficulties after starting silodosin or any prostate medication

• Changes in ejaculation, including reduced volume, absent ejaculation, or retrograde ejaculation

• Reduced libido or loss of interest in sexual activity

• Relationship difficulties related to sexual function

• Anxiety or low mood associated with sexual side effects

Preparing for your appointment: Consider keeping a brief record of when symptoms occur, their severity, and any patterns you notice. Be prepared to discuss your current medications, overall health, and lifestyle factors. Your GP may need to examine you and arrange blood tests to check testosterone levels, glucose, and lipid profiles.

What your GP can offer:

Your doctor will review whether silodosin remains the most appropriate treatment for your urinary symptoms or whether an alternative medication might better suit your needs. They can discuss the option of adding a PDE5 inhibitor if erectile function is affected, or refer you to a urologist for specialist assessment if symptoms are complex or not responding to initial management.

Do not stop medications without medical advice. Abruptly discontinuing silodosin may cause your urinary symptoms to return. If side effects are troublesome, your GP can create a plan to transition to alternative treatments safely.

Important reminders:

• If you are scheduled for cataract surgery, inform your ophthalmologist about current or previous use of silodosin or other alpha-blockers due to the risk of intraoperative floppy iris syndrome (IFIS)

• Report suspected side effects via the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk)

Seek urgent medical attention if you experience:

• A painful erection lasting more than 4 hours (priapism)

• Sudden loss of vision or hearing

• Sudden severe chest pain during sexual activity

• Severe dizziness or fainting, particularly when standing

Remember that effective treatments exist for both BPH and ED, and with appropriate medical guidance, most men can achieve satisfactory management of both conditions without compromising quality of life.

Frequently Asked Questions