How to Get a Sildenafil Prescription and What You Will Be Asked

Most sildenafil medicines in the UK are prescription-only. Viagra Connect 50mg is available from pharmacies without a prescription, after a pharmacist consultation.

The practical question is therefore not whether you need a prescription. It is what the assessment involves, what will be asked, what makes a prescriber say no, and how long the prescription lasts once you have one.

This page answers all four. It also sets out what the regulator actually requires of the prescriber, which is more than most pages admit and more than a tick-box questionnaire on its own can satisfy.

Key things to know

• Most sildenafil medicines are prescription-only. Viagra Connect 50mg is available from pharmacies after a pharmacist consultation
• An online consultation is a real assessment, not a formality, and a prescriber reviews it before anything is supplied
• The GPhC is explicit that a prescriber must not base the decision on a questionnaire alone
• Refusal is a normal outcome. Nitrate use and certain cardiovascular conditions can make sildenafil unsuitable
• Blood pressure matters both ways. Very low blood pressure and uncontrolled high blood pressure can both make sildenafil unsuitable
• A prescription is time limited, and renewal involves a fresh check rather than an automatic reissue
• Treatment suitability depends on an individual clinical assessment

Is a Prescription Required?

It depends on the product. Most sildenafil medicines are prescription-only, while Viagra Connect 50mg is a pharmacy medicine supplied after a pharmacist consultation.

That classification exists for a specific reason rather than as red tape. Sildenafil lowers blood pressure, and combined with a nitrate it can lower it dangerously. It is also frequently taken by men in the age group most likely to have undiagnosed cardiovascular problems. The assessment is what catches both.

Being physically present in a shop does not change it. A registered pharmacy can only hand over a prescription-only medicine against a prescription, which means an assessment has to have happened first, whether that took place in a consulting room or through an online consultation.

Any seller offering sildenafil with no clinical questions at all is operating outside UK law. The MHRA is direct about it: a medicine that does not come from a registered pharmacy is not safe, and supplying it that way is unlawful.

How to Get a Prescription

There are two ordinary routes, and both end at the same place: a prescriber deciding whether treatment is appropriate for you.

Through an Online Consultation

An online consultation is a structured clinical assessment completed in writing and reviewed by a prescriber. It usually runs in five stages.

1. You complete the assessment. Your medical history, current medicines, and the specific exclusions for this medicine
2. A prescriber reviews it. A UK registered prescriber reads what you submitted and decides whether treatment is appropriate
3. They may come back to you. If something is unclear or incomplete, expect a follow-up question rather than a silent approval
4. A prescription is issued or declined. Both are legitimate outcomes
5. A registered pharmacy dispenses it, and the medicine is supplied with a dispensing label and a patient information leaflet

Through a GP

A GP can assess and prescribe for erectile difficulty, and for some men that is the better route.

It is worth choosing deliberately rather than by default. A GP holds your full medical record, which matters most if your history is complicated, if you take several medicines, or if the difficulty appeared suddenly and might point to something else.

An online route holds only what you tell it, which is why what you disclose matters so much. The two routes are not in competition. They are suited to different situations, and telling your GP about treatment obtained elsewhere keeps your record accurate.

Sildenafil can also be prescribed on the NHS for eligible patients who meet the relevant prescribing criteria.

What the Regulator Requires of the Prescriber

This is the part most pages skip, and it explains why a good consultation asks more than you expect.

The GPhC's guidance for registered pharmacies providing services at a distance requires that prescribers only propose or prescribe treatment when they have adequate knowledge of the person's health and are satisfied it will meet their needs.

It goes further on questionnaires, stating that the prescriber must not base prescribing decisions on the information provided in a questionnaire alone, and must independently verify what the person provides and obtain the information needed to support the decision.

It also expects identity to be checked, with an identity check appropriate for the medicine being supplied.

And it addresses record keeping between services, describing the position where the person has provided their regular prescriber's contact details and consented to them being contacted, with relevant information shared between the professionals involved in their care.

Read together, those requirements are why a legitimate online service asks follow-up questions, why it sometimes declines, and why it asks whether it may inform your GP.

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What You Will Be Asked

The assessment covers four areas. Knowing them in advance makes the process quicker and, more importantly, makes your answers more accurate.

About the Difficulty Itself

• How long it has been happening
• Whether it came on gradually or suddenly
• Whether it happens every time or only in some situations
• Whether it is present on waking

Sudden or situation-dependent difficulty, or preserved erections in some circumstances, can sometimes suggest a psychological component, although these features do not by themselves establish the cause.

In the clinical studies, 84% of men whose difficulty was psychological in origin reported improvement, compared with 59% of men with diabetes. The cause changes what is likely to work.

Your Medical History

• Heart disease, angina, and any previous heart attack or stroke
• Blood pressure, both high and low
• Diabetes
• Liver or kidney problems
• Eye conditions, particularly any inherited degenerative retinal condition
• Any previous loss of vision in one eye
• Bleeding disorders or stomach ulcers
• Any deformity of the penis
• Sickle cell anaemia, leukaemia or multiple myeloma

Each of these appears for a documented reason. Kidney and liver function matter because they change how much medicine reaches the bloodstream: in severe kidney impairment the exposure roughly doubles, and in cirrhosis it rises by around 85%.

Every Medicine You Take

This is the question most often answered incompletely, and it is the one that matters most.

• Nitrates and nitric oxide donors. An absolute exclusion, with no safe interval. This includes nicorandil and amyl nitrite
• Riociguat. Also an absolute exclusion
• Alpha blockers, often taken for blood pressure or prostate symptoms. Not an absolute exclusion, but the product information states that patients should be stabilised on alpha blocker therapy before sildenafil is started
• Medicines that raise sildenafil levels, including certain antibiotics and antifungals
• Anything bought without a prescription, including supplements and anything obtained online

Occasional medicines count. A nitrate spray used only when needed is still a nitrate.

Your Blood Pressure

Blood pressure is checked in both directions, and both directions can stop a prescription.

Sildenafil produces mild and transient decreases in blood pressure. In the studies the mean maximum decrease in supine systolic pressure was 8.4 mmHg, with 5.5 mmHg diastolic, which in the majority of cases does not translate into clinical effects.

That is fine on a normal blood pressure. It is not fine on a low one. Low blood pressure is a contraindication, and so is uncontrolled high blood pressure.

You may be asked for a recent reading. If you do not have one, getting one before the consultation is the single most useful thing you can do to speed it up.

What Is Being Screened For

The assessment is doing three jobs at once, and only one of them is about the medicine.

What it checks	Why
Absolute exclusions	Nitrates and certain cardiovascular conditions make treatment unsafe
Cardiovascular fitness	Erectile difficulty can be an early sign of circulatory disease
Underlying cause	Diabetes, hormonal and psychological causes respond differently
Interactions	Several common medicines change sildenafil levels
Whether treatment is appropriate at all	Sometimes the answer is investigation, not a tablet

The second row deserves emphasis. Erectile difficulty can appear before other signs of circulatory disease, which is why the product information notes that it is important to have a check-up with a prescriber within the first 6 months of using sildenafil. A prescription is not the end of the matter.

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Why a Prescription Might Be Refused

Refusal is a normal and appropriate outcome, and understanding why makes it less frustrating.

Reasons That Rule Treatment Out Entirely

• Taking a nitrate or nitric oxide donor in any form, including occasional sprays
• Taking nicorandil, amyl nitrite or riociguat
• Low blood pressure
• Recent stroke or recent heart attack
• Severe liver impairment
• Known hereditary degenerative retinal disorders
• Previous loss of vision in one eye from a specific condition affecting the optic nerve
• Any condition where physical exertion is inadvisable on cardiovascular grounds

These are contraindications or exclusion criteria that a prescriber must take into account.

Reasons That Mean Not Yet

• Uncontrolled high blood pressure, which needs bringing under control first
• Not yet stabilised on an alpha blocker, where the product information requires stabilisation before sildenafil is started
• Unexplained symptoms that need investigating in their own right
• Incomplete information, where the prescriber cannot make a safe decision on what was provided
• Chest pain on exertion that has not been assessed

These situations may require further assessment or treatment before sildenafil can be considered.

What to Do if a Prescription Is Refused

Ask which category it falls into. That single question tells you whether you are looking at a permanent exclusion or something addressable.

If it is addressable, the next step is usually a blood pressure reading, a review of another medicine, or an appointment with your GP. If it is absolute, the honest position is that a different supplier will not change the answer, and looking for one that will is looking for a supplier that does not check.

Non-tablet options exist for men who cannot take medicines in this class, and those are assessed separately. The full range of licensed options is on the erectile dysfunction treatments page.

Strength and Quantity

Searches for a particular strength usually assume it is something you select. It is not.

Which strength is appropriate is decided in the assessment, based on your history, your other medicines, your kidney and liver function and your circumstances. Your prescriber will determine the appropriate treatment.

The same applies to quantity. The number of tablets on a prescription reflects a clinical judgement about a review interval, not a bulk purchase decision. Stay with the strength and quantity on your dispensing label rather than adjusting either yourself, never take more than one tablet in any 24-hour period, and never take two tablets of a lower strength to make up a higher one.

If a strength is not working after several proper attempts, that is information for your prescriber. It is not a reason to change anything on your own.

How Long Does a Prescription Last?

A prescription for sildenafil is time limited in two separate senses, and they are often confused.

The first is the validity of the prescription itself, which is the period within which it can be dispensed. The second is the review interval, which is how long the prescriber is content for you to continue before being reassessed.

The second is the one that matters for ongoing treatment. A prescriber issues enough for a defined period and then wants to know how things have gone, whether anything has changed, and whether treatment should continue.

Prescriptions for Younger Men

Sildenafil is licensed for adult men aged 18 and over, so anyone under 18 falls outside the licence entirely and no prescriber should supply it.

For men over 18 but younger than the typical age of presentation, the medicine is not the interesting question. The cause is.

Erectile difficulty in a younger man is more likely to have a psychological component, and it is also more likely to be worth investigating, because circulatory or hormonal causes appearing early deserve attention rather than a tablet on its own. Expect a good assessment to spend more time on cause and less on product, and expect that to be the right thing rather than an obstacle.

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What You Are Paying For

When sildenafil is obtained privately, the person receiving it pays for the treatment. Eligible patients may also receive it through NHS prescribing.

Two points are worth understanding before comparing anything.

The first is that the clinical assessment is part of a lawful supply, not an optional extra.

The second is that eligibility for treatment is a clinical question, not a commercial one. What determines whether you can have sildenafil is your medical history and your current medicines, and no supplier can change that answer.

Our standard prices are published per pack, with no separate delivery charge on standard orders, and every order is supplied in plain unbranded packaging. Check the live figure for the pack you want, because prices change.

Why Buying Outside the System Is the Real Risk

The alternative to being assessed is not a faster prescription. It is an unassessed supply, and the regulator has published what that looks like at scale.

Between 2021 and 2025 the MHRA's Criminal Enforcement Unit seized around 19.5 million doses of illegally traded erectile dysfunction pills, including 4.4 million in 2025 alone. Those products may contain no active ingredient, the wrong dose, hidden medicines or toxic ingredients, and can raise the risk of heart attack, stroke and dangerously low blood pressure.

The MHRA's advice is to use only UK-registered pharmacies, and to avoid buying medicines from social media, messaging apps or unknown websites.

You can check a pharmacy's registration number against the register the GPhC publishes. Ours is 9012878. That check takes two minutes and it is the most useful thing you can do before ordering anything.

Safety Points Worth Knowing

Sildenafil works by increasing blood flow to the penis, and only when you are aroused. Avoid grapefruit and grapefruit juice, because they can affect sildenafil levels, and excessive alcohol can make it harder to achieve an erection.

Common side effects include headache, flushing and nasal congestion. Serious reactions, including severe allergic reactions, are uncommon but need urgent medical attention.

Sildenafil is also prescribed for pulmonary arterial hypertension, at different strengths and under specialist care. Those products are not interchangeable with the erectile dysfunction medicine.

Seek medical attention immediately for chest pain, fainting, an erection lasting longer than 4 hours, a sudden decrease or loss of vision or hearing, or an allergic reaction. This medicine should only be used under the supervision of an appropriately qualified prescriber.

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