Sildenafil tablets for erectile dysfunction
Sildenafil is a prescription-only tablet for erectile dysfunction, and the same active ingredient as Viagra. It's taken about an hour before sex, and only works when you're aroused.2
From £4.68 a month
Check your eligibility →- CQC registered
- UK-registered clinicians
- Plain, discreet delivery
All content on this page has been medically reviewed by Naeem Teni, Clinical Lead. GPhC 2215591.
What is Sildenafil?
Sildenafil is a prescription-only tablet for erectile dysfunction, and the same active ingredient as Viagra. It's taken about an hour before sex, and only works when you're aroused.2
A clinician reviews your assessment before anything is prescribed, and is there if you have questions along the way.
How does Sildenafil work?
- Blood flow, not desire. An erection depends on blood flowing into the penis. Sildenafil helps the blood vessels there relax, so more blood can reach where it's needed.2
- It blocks an enzyme called PDE5. When you're aroused, your body makes a messenger that keeps those vessels open. PDE5 breaks it down. Sildenafil slows PDE5, so the effect holds.2
- Arousal still has to happen. It won't cause an erection on its own. You still need to be sexually stimulated.
- It treats the symptom, not the cause. ED can be an early sign of heart or blood-sugar problems, which is why a clinician looks at the whole picture first.
How much does Sildenafil cost?
Your clinician sets the strength. The bigger the pack, the less each one costs.
25mg
50mg
100mg
How do I use Sildenafil?
- Plan ahead. Take it about an hour before sex.2
- Watch the meal. A big or fatty meal beforehand can delay it working.2
- One a day, max. No more than one dose in 24 hours.2
- Give it a few tries. It doesn't always work the first time. If it isn't helping, your clinician can adjust the dose.
Drinking? A lot of alcohol makes erections harder to get, with or without treatment.
How does Sildenafil compare with other options?
Trial figures come from different studies in different men, so they aren't a direct ranking. Your clinician will talk through which suits your routine.
| Compared on | Sildenafil | Tadalafil |
|---|---|---|
| In trials | 82% at 100mg1 | 81% at 20mg3 |
| Key points | About 1 hour before sex A few hours | At least 30 minutes before sex Up to 36 hours |
| Price | From £4.68 | From £11.36 |
| Medicine page | This page | View Tadalafil → |
Is Sildenafil right for me?
It isn't suitable for everyone. Your assessment covers all of this, and a clinician checks your answers before anything is prescribed.
Usually suitable if
- You're an adult (18 or over) living in the UK.
- You've had trouble getting or keeping an erection often.
- You're happy for a clinician to look at what might be causing it, not just treat the symptom.
- A clinician judges it safe with your health history and anything else you take.
Not suitable if
- You take nitrates (for chest pain or heart conditions), the combination can be dangerous.
- You have certain heart or blood-pressure conditions a clinician will ask about.
- You're allergic to sildenafil or any of its ingredients.
- A clinician decides the possible side effects or risks outweigh the benefit.
Not sure?
Let a clinician check for you
You don't need to work it out yourself. The online assessment asks the right questions, and a UK clinician reviews your answers before anything is prescribed.
Start my assessment →What are the side effects of Sildenafil?
Most side effects are mild and pass as the tablet wears off.2
More common
Usually mild and short-lived
Rare
Get help straight away if
- An erection lasting more than 4 hours. This needs urgent treatment to avoid lasting damage.
- Sudden loss of vision in one or both eyes.
- Sudden loss or reduction of hearing, sometimes with ringing or dizziness.
- Chest pain during or after sex. Stop, sit up, and don't use a nitrate spray.
Never with nitrates or poppers. Taking sildenafil with nitrates (for chest pain) or poppers can drop your blood pressure dangerously.2
Sildenafil FAQs
Is Manova a proper clinic, or a website?
Both. We’re a CQC-registered clinic that happens to live online. Every prescription is signed off by a registered clinician, not an algorithm.
Will it turn up in a branded box at my office?
No. Plain brown packaging, no Manova branding, no clue what’s inside. Sent to a home or pickup address, your call.
What if the clinician says no?
Then they say no, and you’re not charged: the hold on your card is released. They might suggest a safer alternative, more tests, or refer you back to your GP. We’d rather lose a customer than push the wrong treatment.
Am I locked into a contract?
No. There’s no contract and no minimum term. Your plan renews monthly (or every 3 or 6 months on a longer plan), and you can cancel it yourself from your account at any time. Once it’s cancelled you won’t be charged again.
How is this different from going to my GP?
It isn’t, really. The same medicines, prescribed by registered clinicians to the same standards. We’re just faster to get hold of, and a lot less awkward to talk to about the things on this page.
Read up on Sildenafil
Vardenafil and avanafil: how they differ from sildenafil and tadalafilFour medicines, one mechanism, and a surprisingly small number of real differences. The ones that exist…Read guide →
Sildenafil side effects: what’s common, what’s rare and what needs urgent careMost of what happens is a blood vessel doing what the medicine tells it to. A short list isn’t, and those…Read guide →
Viagra Connect and the other pharmacy ED medicines: what you can buy without a prescriptionThree products, one counter, and a conversation that isn’t a formality. Here’s what the pharmacist is…Read guide →References (3)
- Viagra (sildenafil) European Public Assessment Report, scientific discussion. European Medicines Agency.
- Viagra (sildenafil) Summary of Product Characteristics. Electronic Medicines Compendium (EMC).
- Brock GB, et al. Efficacy and tolerability of tadalafil in men with erectile dysfunction. J Urol. 2002;168:1332–1336.