Sildenafil BNF Guide: Complete ED Treatment Options

Sildenafil, listed in the British National Formulary (BNF), remains the most widely prescribed treatment for erectile dysfunction in the UK. Whether you're considering generic sildenafil or branded Viagra, understanding your options helps you make an informed choice. Both contain the same active ingredient but differ in cost. EverydayMeds offers both generic sildenafil and Viagra, allowing you to choose the option that best suits your needs and budget during checkout.

  • Generic sildenafil offers the same effectiveness as Viagra at a lower cost
  • Multiple dosage strengths available: 25mg, 50mg, and 100mg tablets
  • Works within 30-60 minutes and effects may last 4-6 hours
  • Requires prescription following clinical assessment by UK-licensed prescriber
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Not sure which one? Here's the honest comparison.

Sildenafil
~60 min
~4 hrs
you like to plan ahead
Tadalafil (as-needed)Most prescribed
~30 min
up to 36 hrs
you want a whole weekend covered
Tadalafil Daily
always active
continuous
you never want to think about timing
Vardenafil
~15–30 min
~8 hrs
you want the fastest onset

How ED treatment works in your body.

Increases blood flow

Increases blood flow

When PDE5 is suppressed, blood is able to flow more freely through the body—including to the (you guessed it) penis.

Increase erections

Increase erections

More blood flow to the penis means harder, more satisfying erections once you're sexually stimulated.

Understanding Your Sildenafil Treatment Choices

What is Sildenafil and How Does It Compare to Viagra?

Sildenafil citrate is a PDE5 inhibitor medication that helps treat erectile dysfunction by increasing blood flow to the penis during sexual arousal. The generic version contains exactly the same active ingredient as Viagra but typically costs significantly less. Both medications work identically - the main difference lies in branding and price. Many patients choose generic sildenafil for its cost-effectiveness, whilst others prefer the branded option. At EverydayMeds, you can select either generic sildenafil or Viagra during your order, giving you complete flexibility.

Available Dosages and How They Work

Sildenafil is available in three strengths: 25mg, 50mg, and 100mg tablets. Most men start with 50mg, taken approximately one hour before sexual activity. Your prescriber may adjust this to 25mg if you experience side effects, or increase to 100mg if 50mg proves insufficient. The medication works by blocking the PDE5 enzyme, which helps maintain increased blood flow when you're sexually aroused. It's important to note that sildenafil doesn't cause automatic erections - sexual stimulation is still required for it to be effective.

Clinical Assessment and Eligibility

Before prescribing sildenafil, a qualified healthcare professional must assess your suitability through a clinical consultation. This evaluation considers your medical history, current medications, and cardiovascular health. The assessment helps ensure sildenafil is safe and appropriate for your individual circumstances. Men taking certain medications, particularly nitrates for heart conditions, cannot safely use sildenafil due to potentially dangerous interactions that could cause severely low blood pressure.

Effectiveness and What to Expect

Clinical studies show that sildenafil helps approximately 70-80% of men with erectile dysfunction achieve erections sufficient for sexual activity. The medication typically begins working within 30-60 minutes of taking it, with peak effectiveness occurring around one hour after consumption. Effects may last up to 4-6 hours, though this doesn't mean you'll have an erection for this entire duration. Taking sildenafil with a large or fatty meal may delay its onset of action.

Cost Considerations and Value

Generic sildenafil offers substantial savings compared to branded Viagra whilst providing identical therapeutic benefits. The cost difference can be significant over time, making generic sildenafil an attractive option for many patients. Both formulations undergo the same rigorous quality standards and contain identical amounts of active ingredient. Your choice between generic sildenafil and Viagra often comes down to personal preference and budget considerations, as both are clinically equivalent in terms of safety and effectiveness.

What you need to know about erectile dysfunction

It's one of the most common conditions we treat, and one of the most treatable.

What is Erectile Dysfunction?
ED means finding it hard to get or keep an erection firm enough for sex. It's not unusual to have an off night; the point at which it's worth doing something is when it's happening regularly, or when it's starting to bother you.
How will I feel when I take ED medication?
For most men, nothing feels different day to day. The medication works in the background — when you're sexually aroused, it helps blood flow where it's needed, so erections come more easily and last longer. It doesn't cause arousal on its own. Some men notice mild, short-lived effects like a headache, facial flushing or a stuffy nose, which usually pass as the dose wears off.
Why do I need a prescription for ED medication?
ED treatments are prescription-only medicines in the UK because they aren't suitable for everyone — for example, alongside certain heart conditions or medications like nitrates. That's why we ask you to complete a short online consultation first. A UK-registered prescriber reviews your answers to make sure your chosen treatment is safe and right for you before it's dispensed.
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