Why Does Erectile Dysfunction Happen?
An erection depends on blood flow, nerves, hormones, sexual stimulation and psychological wellbeing working together. Erectile dysfunction can happen when one or more parts of that process are affected — which is why understanding the cause matters before deciding what to do next.
Erectile dysfunction (ED) means repeatedly having difficulty getting or maintaining an erection firm enough for satisfactory sexual activity. It can be associated with reduced blood flow, diabetes and metabolic health, cardiovascular risk, hormone problems, neurological conditions, medicines, psychological factors or a combination of causes.
Occasional erection difficulty does not necessarily mean that a man has persistent ED. When the problem keeps happening, however, it is worth investigating rather than simply assuming it is caused by age or stress.
An erection is a whole-body process
Erectile function is not controlled by one hormone or one blood vessel. The brain, nerves, circulation, erectile tissue and hormones all contribute. Psychological and relationship factors can also influence the process.
Blood flow
Penile arteries need to dilate so blood can enter the erectile tissue. Vascular disease and cardiovascular risk factors can interfere with this.
Nerve signalling
Nerve signals connect sexual stimulation with the vascular changes required for an erection. Neurological disease or nerve injury can affect this pathway.
Hormones
Testosterone is particularly important for sexual desire and normal sexual function. Hormonal problems can contribute to ED in some men.
Glucose & metabolic health
Diabetes can affect both blood vessels and nerves, making glucose and HbA1c relevant investigations in appropriate men with ED.
Medicines & health conditions
Some medicines and underlying medical conditions can contribute to erection problems. Medication should not be stopped without appropriate medical advice.
Psychological factors
Stress, anxiety, depression, performance anxiety and relationship factors can affect erections — sometimes alongside a physical cause.
How does an erection happen — and where can ED occur?
This pathway explains why erectile dysfunction can have several different causes. A problem at more than one stage can also occur at the same time.
The erection pathway
Sexual stimulation starts a coordinated chain of neurological and vascular events. Successful erections depend on the pathway working effectively.
Common questions men ask about erectile dysfunction
These are some of the most common questions men ask when erections become less reliable. Tap each question for a direct clinical answer.
How to increase blood flow to the penis?
Penile blood flow is closely linked to vascular health. Depending on the individual, improving cardiovascular risk factors — including physical activity, weight, smoking, blood pressure, cholesterol and glucose control — may support erectile health.
Established ED treatments such as PDE5 inhibitors can improve the erectile response to sexual stimulation in suitable patients. Selected men with blood-flow-related ED may also consider low-intensity shockwave therapy after appropriate assessment.
At MDC: men can access ED investigation and focused shockwave therapy in Baker Street.
How can you tell if a man has erectile dysfunction?
ED is generally characterised by persistent difficulty achieving or maintaining an erection sufficient for satisfactory sexual activity. One unsuccessful erection does not establish erectile dysfunction.
Patterns matter: how often it happens, whether morning erections remain, whether erections differ during masturbation and partnered sex, libido, medicines and other health symptoms can all provide useful information.
If the problem is persistent, an assessment can help determine the next step.
What vitamins are good for erectile strength?
No vitamin should be presented as a proven general treatment for erectile dysfunction. A deficiency should be identified and treated appropriately, but taking large amounts of vitamins without evidence of deficiency is not a substitute for investigating ED.
If erections have changed, cardiovascular, metabolic, hormonal, neurological and psychological factors may be more important than supplements.
The better question is not “Which vitamin improves erections?” but “Why has my erectile function changed?”
What causes a man to lose a hard-on?
Losing an erection during sex can happen occasionally and does not necessarily indicate disease. Possible contributors include distraction, anxiety, stress, alcohol, tiredness, reduced stimulation or relationship factors.
When it happens repeatedly, physical factors such as reduced penile blood flow, diabetes, medication effects or hormonal problems may also need to be considered.
Persistent difficulty maintaining an erection is one of the common presentations of ED.
Can lack of testosterone cause erectile dysfunction?
Low testosterone can contribute to sexual symptoms, particularly reduced libido, and may contribute to erectile difficulties in some men. However, testosterone is only one part of erectile function.
ED can occur despite a normal testosterone level, which is why vascular, metabolic, medication and psychological factors may also need consideration.
Testosterone testing is usually most useful when interpreted alongside symptoms and, where appropriate, other hormone measurements.
How long does erectile dysfunction last?
There is no single duration. Temporary erection difficulty may resolve when a short-term contributor such as stress, illness, tiredness or alcohol is removed.
Persistent ED can continue until contributing factors are identified and appropriately managed. Duration therefore depends heavily on the cause, general health and treatment response.
If ED is continuing rather than being an isolated event, it is reasonable to seek assessment.
At what age do people get erectile dysfunction?
Erectile dysfunction can occur at different ages. It becomes more common with increasing age, but persistent ED should not simply be dismissed as an inevitable part of getting older.
Younger men can also experience ED, including through psychological, hormonal, metabolic, medication-related and vascular factors.
The clinically useful question is therefore not simply your age, but what is contributing to the change in your erections.
Can Viagra cure erectile dysfunction?
Sildenafil (Viagra) is an established PDE5 inhibitor used to treat ED. It helps support the erectile response to sexual stimulation but should not automatically be described as curing the underlying cause.
Some men respond very well to medication. Others may need the way they are taking it reviewed, further investigation or an alternative treatment.
PDE5 inhibitors are not suitable for everybody and can interact dangerously with nitrate medicines, so appropriate medical prescribing and advice are important.
What blood tests may be useful for erectile dysfunction?
Not every man with ED needs every blood test. Testing should be selected according to symptoms, medical history, examination and clinical assessment.
Erectile Dysfunction / Impotence Profile
MDC’s dedicated ED blood profile examines hormonal, metabolic and cardiovascular factors that may be relevant when investigating erectile dysfunction.
Blood sample · Baker Street · London
Current MDC profile includes
These markers do not diagnose every cause of ED. They provide information that can be interpreted alongside symptoms and clinical assessment.
Why can ED be worth investigating even if medication works?
Penile erection depends heavily on healthy vascular function. For some men, erectile difficulties coexist with cardiovascular or metabolic risk factors such as diabetes, abnormal glucose regulation, high cholesterol, smoking, obesity or hypertension.
This does not mean that every man with ED has cardiovascular disease. It does mean that persistent ED should sometimes be viewed as an opportunity to consider wider health rather than treating it only as a bedroom problem.
What about shockwave therapy for erectile dysfunction?
Low-intensity shockwave therapy uses acoustic waves applied externally to penile tissue. It is a non-surgical treatment considered particularly in selected men where reduced blood flow contributes to erectile dysfunction.
It is not a guaranteed cure, and it is not equally appropriate for every type of ED. Current European urology guidance describes a potential mild improvement in selected men with vasculogenic ED, while the strength of recommendation remains limited.
MDC provides focused shockwave therapy for ED in London. Suitability should be considered in the context of the individual’s symptoms, health and treatment history.
What should I do if I have erectile dysfunction?
You do not need to know whether your ED is hormonal, vascular or psychological before contacting us. That is what the assessment pathway is designed to help establish.
Tell us what’s happening
How long has ED been happening? Can you get an erection, maintain it, and do you still experience morning erections?
Investigate where appropriate
Blood testing may examine hormones, glucose, cardiovascular risk and other relevant factors.
Specialist assessment
Urology or andrology input may be appropriate depending on symptoms, findings and treatment history.
Choose treatment
The pathway may involve medication, risk-factor management, focused shockwave therapy or another clinically appropriate option.
Speak to the MDC team about erectile dysfunction
You do not need to diagnose yourself before getting in touch. If you are unsure whether you need an ED blood test, testosterone testing, shockwave therapy or specialist urology/andrology assessment, contact Marylebone Diagnostic Centre and our team can help guide you towards the appropriate pathway.
Your enquiry can be handled discreetly. Simply tell us: “I’d like help with erectile dysfunction.”
Don’t just treat the erection. Understand what may be causing the problem.
MDC provides a discreet erectile dysfunction pathway in Central London, including ED blood testing, hormone assessment, focused shockwave therapy and access to appropriate specialist pathways.
