Erectile Dysfunction

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Erectile Dysfunction

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Before you start a diagnosis, please read all of the information below.

Most men will experience occasional times when they are unable to get an erection. This can be due to alcohol, stress or tiredness. Erectile dysfunction (ED) is the inability to get and/or maintain a proper erection. For most men, this is usually temporary. 

Some men, however, have persistent or recurrent erectile dysfunction. This occurs in about 50% of men between the ages of 40 and 70. ED can occur at any age but is more common with increasing age.  The condition is usually treatable, most commonly by a tablet taken before sex.

Some of the treatments we may prescribe if clinically appropriate:

Please see the Common Treatments section below for more information. 

Most cases (7 out of 10) of ED in the over 40's are due to narrowing of the arteries that take blood to the penis. This is due to a build-up of fatty deposits in these arteries. It is important to address the risk factors for narrowing arteries to help reduce your chances of developing heart disease in the future. 

Common Symptoms

Common Symptoms

  • difficulty in getting an erection
  • difficulty in maintaining an erection
  • anxiety
  • relationship difficulties

Associated underlying factors which should be monitored may include:

  • high cholesterol
  • raised blood pressure
Common Treatments

Possible treatments we prescribe if clinically appropriate:


  • Generic Sildenafil 50mg dose: 4 tablets (£0.63*)   
  • Generic Sildenafil 100mg dose: 4 tablets (£0.72*)  


  • Cialis 10mg dose when needed: 4 tablets (£28.88*)
  • Cialis 20mg dose when needed: 4 tablets (£28.88*)
  • Cialis 2.5mg continual daily dose, take one a day:  28 tablets (£54.99*) 
  • Cialis 5mg continual daily dose, take one a day: 28 tablets (£54.99*)

As part of our safeguarding vulnerable people procedures, you will be required to show photo identification to the pharmacy dispenser when you collect your medication.

*Prices shown are cost price of the medication, taken from the British National Formulary 2018, and are given as a guideline. Pharmacies will add a dispensing fee to this which will vary considerably, so it is worthwhile phoning around to compare prices. The medication is paid for at your chosen pharmacy. 

Please click on the medication above to read the Patient Information Leaflet for important information about each drug. 


Physical Causes of ED

  • Reduced blood flow to the penis. This is the commonest cause in the over 40's. The blood flow is reduced if the arteries become narrow. Age, smoking, high blood pressure and raised cholesterol can all cause your arteries to narrow. 
  • Alcohol excess.
  • Side effects of medication. These include antidepressants, beta-blockers and water tablets.
  • Diabetes. This can affect the blood vessels and nerves in the penis.
  • Cycling. Long distance cycling may affect the function of the nerves.
  • Diseases affecting the nerves to the penis. These include Parkinson's, MS and a stroke.
  • Hormonal causes. This is uncommon and includes lack of testosterone. 

Psychological causes of ED

  • stress at work or home
  • relationship problems
  • anxiety
  • depression

In younger men, psychological problems are most commonly the cause of ED. Usually, mental health issues tend to cause ED to develop fairly suddenly, and will often resolve once the psychological issues have improved. Sometimes ED can worsen anxiety which then leads to a vicious cycle of worsening symptoms.

ED and risk factors for heart disease

7 in 10 cases of ED are caused by narrowing of the arteries (atheroma) in the penis.

Fatty plaques that develop instead the arteries are called atheroma and build up over the years causing narrowing of the arteries and reduce the blood flow. This can most commonly affect the penile arteries leading to erectile dysfunction, the heart arteries and can cause heart attacks, in the brain it can lead to a stroke and in the legs, it can result in peripheral vascular disease.

Certain risk factors if not addressed can increase your chances of developing atheroma which can result in a person developing one or more of the conditions above. The risk factors include:

  • Smoking is one of the major risk factors, and the effects can start early on. Smoking can approximately double your chances of developing ED. There are many methods to help you quit smoking. You can discuss the options with your pharmacist, doctor or Start a Smoking Cessation assessment with i-GP.

  • High blood pressure. Ensure you have your blood pressure checked once a year as untreated high blood pressure can lead to a number of different diseases. You can have your blood pressure checked at your pharmacy, with your nurse or doctor, or you may wish to purchase your own Blood Pressure monitor. 

  • High Cholesterol. Have your cholesterol checked at least 3 yearly. If high then dietary modification or medication may be recommended by your doctor. You can have your cholesterol checked with a simple blood test which can be done by your pharmacist, nurse or doctor.

  • Weight. If you are overweight this can affect your health and cause conditions such as heart disease. Losing weight is advised through improving your diet and increasing cardiovascular exercise. 
  • Lack of exercise. At least 30 minutes of physical activity should be done five times a week, which can include walking, jogging, cycling, dancing etc.

  • Poor diet. A diet full of sugar, unhealthy saturated fats and salt can increase your chances of heart disease and diabetes. Look at improving your diet to include more fruit and vegetables. 

  • Excess alcohol
  • Diabetes
Treatment options for ED


PDE5 inhibitors are used to treat ED and work by increasing the blood flow to the penis. They include sildenafil (Viagra), tadalafil (Cialis), vardenafil (Levitra) and avanafil (Spedra). You may not be able to take these tablets if you have certain other medical conditions or take certain other medicines. This includes nitrates taken for angina including GTN.

Sildenafil is available on the NHS for free. Tadalafil is only prescribed on the NHS for men with certain medical conditions. 

Cream Alprostadil (Vitaros)

Alprostadil cream can be applied to the tip of the penis and the surrounding skin. This should be done five to thirty minutes before sexual activity.

Urethral Alprostadil (Muse)

A small pellet is placed into the urethral tube which is absorbed into the penis usually within 10-15 minutes causing an erection. 


In younger men, psychological issues are commonly the cause of ED. Counselling may be the best option to treat it. Sometimes couples therapy may help if there are underlying relationship issues that need addressing.

Treating the underlying cause

  • treatment for anxiety or depression
  • reducing alcohol intake
  • changing the medication that could be causing the ED

Lifestyle changes

  • treat any underlying high blood pressure
  • treat cholesterol if raised

Vacuum Devices

The penis is placed in a device and the air is sucked out of the container. This causes the blood to be drawn into the penis resulting in an erection. A rubber band is then placed at the base of the penis to maintain the erection.


Tests that should also be done for ED

To rule out underlying causes of erectile dysfunction, the following should be checked:

  • cholesterol level
  • blood pressure
  • blood glucose
  • prostate exam

These can be tested at your GP surgery. Please see your GP to arrange these.

Who should not take sildenafil or tadalafil

You should NOT take sildenafil or tadalafil if you take nitrate medicines. This will include GTN spray, tablets, and patches for chest pain or breathlessness, nitrate tablets such as isosorbide mononitrate or isosorbide dinitrate and nitrate gel or cream including Rectogesic ointment for anal fissures. 

Nitrate medications interact harmfully with the tablets for erectile dysfunction. This can lead to a heart attack, stroke or even death. 

You should not take sildenafil or tadalafil if you have had a recent heart attack, unstable angina, heart failure, a recent stroke, uncontrolled high blood pressure, a low blood pressure (less than 90/50mmHg), an uncontrolled irregular heartbeat, a degenerative retinal disorder or optic neuropathy.

If you have high blood pressure and take medication, called alpha-blockers (doxazosin, indoramin, terazosin or prazosin), then you need to wait until you are on a stable dose. This is because combining alpha-blocking medication with sildenafil or tadalafil can cause a sudden drop in blood pressure.

The combination of tadalafil and doxazosin is not recommended.

Tadalafil and sildenafil contain lactose. Anyone with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take this medication.

Information about sildenafil

Sildenafil works by increasing the blood flow to your penis. It helps by widening the blood vessels in the penis when you are sexually aroused which will cause an erection. Sildenafil will not cause an erection unless you are sexually aroused.

ED (erectile dysfunction) medication will work well for most men. However, they do not work in every case.

Viagra is a branded version of sildenafil.

Before you start the treatment, please read the manufacturers leaflet contained with the medication. This has further information and lists all the potential side effects.

How to take Sildenafil

Sildenafil should only be taken before sexual activity, and it is not suitable for continuous daily use. Take one tablet about an hour before you plan to have sex. It may still be effective for up to five hours after taking the tablet. Do not take more than one dose in 24 hours. 

Sildenafil can be taken either before or after food. However, it may take longer to work if you have just eaten a large meal. Do not drink lots of alcohol before you plan to take sildenafil, as alcohol can affect your ability to get an erection with Sildenafil.

Do not drink grapefruit juice with sildenafil as it can increase the amount of sildenafil in your bloodstream and this makes side-effects more likely.

Do not drive or operate machinery if you develop any dizziness or visual changes such as blurred vision or colour distortion with Sildenafil.

Never give your medication to other people even if their condition appears to be the same as yours.

Possible side effects from sildenafil

Side Effects

Most types of medicines can cause potential side effects. However, not everyone will experience them. The side effects often improve as your body adjusts to the new medicine, but if any of them continue or become troublesome then speak with your doctor or pharmacist.

Common side effects affecting about 1 in 10 men include:

  • a headache
  • flushing, feeling sick, indigestion, blocked nose
  • feeling dizzy, visual changes such as blurred vision or colour distortion

If you experience any other symptoms which you think may be due to the tablets, speak with your doctor or pharmacist for further advice.

Information about tadalafil

Before you start the treatment you must read the manufacturers leaflet contained with the medication. This contains more information about the medication and the potential side effects.

Tadalafil prevents the action of a chemical called phosphodiesterase type 5 in your body, helping to widen the blood vessels improving the flow of blood to the penis after sexual stimulation. Tadalafil helps to maintain an erection. Cialis is a branded version of tadalafil. 

Tadalafil can be taken in two ways:

  • Before sexual activity. It is available in two strengths for this purpose; 10mg and 20mg tablets. These tablets are not suitable for continuous daily use. You should take one tablet at least half an hour before you plan to have sex. Tadalafil may still be effective up to 36 hours after taking the 10mg or 20mg strength tablet. Do not take more than one dose in 24 hours. If tadalafil 10mg does not produce an adequate effect then 20 mg might be tried.
  • Continuous daily use. There are two strengths available for this purpose; 2.5mg and 5mg tablets. Take one tablet every day at the same time of day. This can be used in men who anticipate a frequent use of tadalafil (at least twice weekly) based on patient choice. The lowest dose should be started and increased if the effect is not adequate.

How to take tadalafil

Tadalafil can be taken either with or without food. Swallow the tablet with a drink of water.

Do not drink grapefruit juice with tadalafil because there is a chemical in grapefruit juice which can increase the levels of tadalafil in your bloodstream, making side-effects more likely.

Tadalafil will not cause an erection unless you are sexually aroused, therefore you will still need to engage in foreplay.

Drinking too much alcohol before taking tadalafil can reduce your ability to get an erection. Only drink in moderation to ensure maximum benefit from the medication.

Do not drive or operate machinery if you develop any dizziness or visual changes such as blurred vision or colour distortion.

Starting tadalafil

When starting tadalafil for the first time it is best to start on the lowest dose for the method in which you have chosen to take it. That is, 10mg if to be taken as and when needed before sexual activity and the 2.5mg dose if taken continuously on a daily basis. You can then judge whether this dose is adequate and discuss this with your doctor.

If you are using any other products or taking any other medicines to treat erectile dysfunction then you should not take tadalafil. 

Never give your medication to other people even if their condition appears to be the same as yours.

Possible side effects from tadalafil

Most types of medicines can cause potential side effects. However, not everyone will experience them. The side effects often improve as your body adjusts to the new medicine, but if any of them continue or become troublesome then speak with your doctor or pharmacist.

Common side effects from tadalafil include:

  • a headache
  • muscle aches and pains
  • indigestion
  • flushing
  • nausea
  • nasal congestion
  • dizziness
  • visual problems

Most of these side effects settle fairly quickly.

When to seek urgent advice

If you develop any of the symptoms listed below whilst taking medication for erectile dysfunction, then you must seek urgent medical advice immediately (from your GP, Out of Hours Service, Urgent care centre, NHS 111). Call an ambulance or go to A&E if the symptoms are severe.

  • chest pains
  • sudden loss of vision
  • if your erection lasts more than 4 hours
Allergic reaction to medications

An itchy rash, swollen face or mouth, or difficulty in breathing, may be signs that you are allergic to the medication. 

Please note that i-GP DOES NOT TREAT Medical Emergencies. 

If you develop a sudden onset of any of the symptoms below then you must STOP the medication immediately and seek urgent medical advice. This could be from your GP, Out of Hours Service, Urgent Care Centre or NHS 111. Call an ambulance or go to A&E if the symptoms are severe.

  • Wheeze
  • Difficulty in Breathing
  • Swelling of the eyelids, face or lips
  • A rash particularly if affecting your entire body
Find sexual health services near you

Please use the following links to find your nearest Sexual Health/ GUM clinic.

You can call the national sexual health helpline free on 0300 123 7123 for further advice if you are worried.

SH:24 is a free online sexual health service, delivered in partnership with the NHS. They provide free test kits, information and advice - 24 hours a day.

Help for Abuse

What is abuse?

Abuse is anything another person does that's meant to cause harm. But it's not always easy to know what's abuse or what to do about it.

There are many types of abuse from physical, emotional, sexual, neglect or domestic. Abuse is always wrong and must be stopped. It is important to take the first step and seek help. If you are in immediate danger call 999.

You can find out more about the types of abuse and where you can access help on the YoungMinds Website.


Domestic violence and abuse

If you are experiencing domestic violence or know of someone that may be experiencing abuse that may need help or support then you can contact the following 

Help after rape or sexual assault

Please see the NHS website for further information.

  • In an emergency call 999
  • You can contact the non-emergency police number 101
  • Or call NHS 111 for further advice

For specialist medical attention and sexual violence support, you would need to be seen at a sexual assault referral centre (SARC). You can find your nearest one here.



Childline is there to help anyone under 19 in the UK with any issue they’re going through. Whether it’s something big or small, or are worried that you may be going through abuse, their trained counsellors are there to support you.

Childline is free, confidential and available any time, day or night. You can talk to them:

  • by calling 0800 1111
  • by email
  • through a 121 Webchat

If you are worried about a child, don't wait until you are certain. If you have any concerns or suspicions, contact the NSPCC free helpline service to speak to an NSPCC counsellor 24/7 or report your concern online here.

If you think a child is in immediate danger don't delay – call the police on 999.

Modern Slavery Helpline

If you think you are a victim of modern slavery/human trafficking contact the modern slavery helpline. They can help you to understand what is available including information, advice and, ways to access government-funded support. The Modern Slavery Helpline is confidential, but, if you don't want to give your name, that is fine. Find out more here.

Call free 24/7 on 08000 121 700 to get help, report a suspicion or seek advice.

Female genital mutilation (FGM)

FGM is abuse and illegal under the UK law. All girls and women have the right to a life free from pain, period problems and difficulties with childbirth that are caused by female genital mutilation.

Female genital mutilation, female circumcision or ‘cutting’ may cause serious health and emotional consequences that last a lifetime. You can stop it. For advice, support or to report it, call the free 24-hour anonymous FGM helpline on 0800 028 3550. Find out more about it here.

Protecting young people from sexual


It is important that young people are kept safe from sexual exploitation. Child sexual exploitation doesn't always involve physical contact and can happen online. It can be stopped and it is everyone's responsibility to report any concerns.

Child sexual exploitation is a hidden crime and can be difficult to identify. Young people often trust their abuser and don't understand that they're being abused. They may depend on their abuser or be too scared to tell anyone what's happening. You can find out more about here.

If you are worried about a child then contact the NSPCC trained helpline counsellors for 24/7 help, advice and support on 0808 800 5000 or email

Watch the NSPCC video sharing the story of a young person who has been groomed and sexually exploited.

Start an erectile dysfunction diagnosis

Do you require treatment for erectile dysfunction?

We could assess your suitability and send you a treatment plan with a prescription, if appropriate, within an hour to your chosen pharmacy.