Erectile Dysfunction: Causes, Assessment and Treatment Options

Erectile dysfunction, often shortened to ED, is the persistent difficulty achieving or maintaining an erection firm enough for satisfactory sexual activity.

An occasional unreliable erection is common and may simply reflect tiredness, stress, excessive alcohol or relationship pressures. When the problem becomes persistent, however, it deserves proper assessment. ED can affect confidence, intimacy and relationships, but it is important to remember that it is a medical condition, not a personal failure, and effective treatment is available.

How does an erection normally occur?

An erection depends on several systems working together:

Sexual interest and stimulation in the brain
Healthy nerves carrying signals to the penis
Adequate blood flow into the erectile tissue
Relaxation of smooth muscle within the penis
Healthy hormone levels
Sufficient trapping of blood to maintain firmness

A problem at any point in this pathway can contribute to erectile dysfunction. Many men have more than one contributing factor.

How does erectile dysfunction present?

Men may notice:

Difficulty achieving an erection
An erection that is not sufficiently firm for penetration
Loss of firmness during sexual activity
Erections that are inconsistent or unpredictable
Reduced spontaneous or morning erections
A longer time or greater stimulation needed to become erect
Anxiety about sexual performance
Reduced sexual desire
Avoidance of intimacy because of embarrassment or fear of failure

ED does not necessarily mean that a man has lost his libido, ability to orgasm or ability to ejaculate. These are separate aspects of sexual function, although they may sometimes be affected by the same underlying condition.

What causes erectile dysfunction?

Blood-vessel and cardiovascular conditions

Because the penile arteries are relatively small, erectile difficulties can occasionally appear before more obvious symptoms of cardiovascular disease.

Associated conditions include:

High blood pressure
High cholesterol
Diabetes
Obesity
Smoking
Physical inactivity
Coronary artery disease
Peripheral vascular disease

For this reason, a new and persistent change in erections should not simply be dismissed as ageing. It can be an opportunity to identify and treat previously unrecognised cardiovascular risk factors.

Neurological causes

Normal erections require intact nerve pathways. ED may occur with:

Diabetic nerve damage
Multiple sclerosis
Parkinson’s disease
Spinal cord injury
Pelvic nerve injury
Previous stroke
Surgery involving the prostate, bladder or rectum

Hormonal and medical conditions

Low testosterone can contribute to reduced sexual desire and may sometimes worsen erections, although testosterone deficiency is not the cause of every case of ED.

Other relevant conditions include:

Pituitary or testicular disorders
Thyroid disease
Chronic kidney or liver disease
Obstructive sleep apnoea
Peyronie’s disease
Chronic pelvic pain

Medication-related erectile dysfunction

Medicines that can sometimes contribute include:

Some antidepressants
Certain blood-pressure medicines
Anti-androgen treatments
Some prostate medications
Opioid pain medicines
Certain antipsychotic medicines

Do not stop a prescribed medicine without first discussing it with your doctor. In many cases, an alternative medication or dose adjustment may be possible.

Psychological and relationship factors

The mind is an important part of the erection pathway. Stress, depression, anxiety, relationship tension and fear of sexual failure can all interfere with erections.

A common cycle can develop:

An erection is lost on one occasion.
The man worries that it will happen again.
Attention shifts from pleasure to monitoring the erection.
Anxiety increases and the erection becomes less reliable.

Psychological and physical causes frequently coexist. Describing ED as “psychological” does not mean that the symptoms are imaginary.

Lifestyle and situational factors

Other contributors include:

Excessive alcohol
Recreational drug use
Smoking or vaping nicotine
Poor sleep
Fatigue
Sedentary lifestyle
Weight gain
Relationship stress
Pornography-related arousal patterns in selected men

How is erectile dysfunction assessed?

Assessment begins with a private and respectful discussion about:

When the problem began
Whether it developed suddenly or gradually
The quality of morning and spontaneous erections
Sexual desire, ejaculation and orgasm
Current relationships and psychological wellbeing
Medical conditions and previous operations
Prescription medicines and supplements
Smoking, alcohol and recreational drugs
Previous treatments and their results

Examination may include blood pressure, weight, cardiovascular assessment, genital examination and evaluation of the prostate when appropriate.

Blood tests may include:

Fasting glucose or HbA1c
Cholesterol and triglycerides
An early-morning testosterone level
Additional hormone tests if testosterone is low
Kidney, liver or thyroid testing when clinically indicated

Specialised testing—such as penile Doppler ultrasound—is not required for every man but may be useful when the diagnosis is unclear, following pelvic trauma, before reconstructive treatment or when initial therapies have failed.

Lifestyle changes: treatment for the whole man

Lifestyle measures can improve erections while also reducing cardiovascular risk. Useful changes include:

Stopping smoking
Limiting excessive alcohol
Exercising regularly
Reducing abdominal weight
Improving sleep
Treating sleep apnoea
Optimising diabetes, cholesterol and blood pressure
Reviewing potentially contributing medications
Addressing stress, depression and relationship difficulties
Cutting out pornography

Pelvic-floor muscle training may help selected men, particularly after prostate surgery, provided the exercises are taught and performed correctly.

Lifestyle improvements may not completely reverse established nerve or vascular damage, but they make other treatments more effective and improve general health.

Oral medications available in Australia

Prescription phosphodiesterase type 5 inhibitors—usually called PDE5 inhibitors—are generally the first medication considered. They improve the natural erectile response by increasing blood flow to the penis.

Medicines available in Australia include:

Sildenafil: usually taken when required and has a relatively short duration of action.
Tadalafil: may be taken when required or as a lower daily dose. Its longer duration can provide greater spontaneity.
Vardenafil: another shorter-acting option taken before anticipated sexual activity.
Avanafil: a more rapid-onset PDE5 inhibitor that may be suitable for selected patients, subject to availability.

These medicines require sexual stimulation; they do not automatically cause an erection and are not treatments for low sexual desire.

Possible adverse effects include:

Headache
Facial flushing
Nasal congestion
Indigestion
Dizziness
Temporary visual disturbance, particularly with sildenafil
Muscle or back discomfort, particularly with tadalafil

PDE5 inhibitors must not be taken with nitrate medication used for angina. Combining them can cause a dangerous fall in blood pressure. Extra caution is necessary in men using certain alpha-blockers, those with unstable cardiovascular disease and those advised that sexual activity is medically unsafe.

A tablet should not be declared ineffective after one poorly timed attempt. The correct dose, timing, food intake, sexual stimulation and several properly conducted trials should be reviewed with the prescribing doctor.

Testosterone treatment

Testosterone replacement should only be considered when symptoms are accompanied by repeatedly confirmed low morning testosterone levels and an appropriate clinical assessment.

Giving testosterone to a man with normal levels is unlikely to correct ED and may cause harm. Treatment also requires consideration of fertility, prostate health, blood count, sleep apnoea and cardiovascular factors.

Vacuum erection devices

A vacuum erection device consists of a cylinder placed over the penis and a pump that creates negative pressure, drawing blood into the erectile tissue. A constriction ring is then placed around the base of the penis to maintain the erection.

Advantages include:

No systemic medication
Usefulness after prostate surgery
Suitability for some men who cannot take tablets
A non-surgical, reusable treatment

Possible disadvantages include bruising, numbness, discomfort, a cooler-feeling penis and an erection that may feel less natural. The constriction ring should generally not remain in place for longer than 30 minutes.

Penile injection therapy

When tablets are unsuitable or ineffective, medication can be injected directly into the side of the penis using a very fine needle. Alprostadil is a commonly used agent. Specialist-supervised compounded preparations may contain combinations of vasoactive medicines.

The injection relaxes penile smooth muscle and can produce a reliable erection independently of sexual stimulation. The dose must be carefully determined, and patients should receive hands-on instruction before using injections at home.

Potential complications include:

Penile discomfort
Bruising or bleeding
Scar tissue or curvature
An erection that is excessively prolonged
Priapism—an erection lasting four hours or more

An erection persisting for four hours is a medical emergency because delayed treatment can permanently damage the erectile tissue. Injection medication should never be sourced or used without appropriate medical supervision.

Intraurethral medication

Alprostadil can also be delivered into the urethra in certain formulations. It avoids a needle but may be less reliable than injection therapy and can cause urethral discomfort. Availability in Australia may vary.

Psychological and sex therapy

Counselling or psychosexual therapy can be very helpful when anxiety, depression, relationship difficulties or previous negative sexual experiences are contributing.

Therapy may be combined with medical treatment. Improving erectile reliability with medication can reduce anxiety, while therapy helps break the cycle of monitoring, fear and avoidance.

Low-intensity shockwave therapy

Low-intensity shockwave therapy has been promoted as a restorative treatment for men with blood-vessel-related ED. Some studies suggest benefit in carefully selected men with mild vasculogenic dysfunction, but protocols vary and long-term evidence remains less certain than for established treatments.

It should not be presented as a guaranteed cure. Patients considering it should discuss the evidence, cost and realistic likelihood of benefit with an appropriately qualified clinician.

Treatments marketed as “regenerative”—including platelet-rich plasma or stem-cell injections—remain inadequately established for routine treatment of ED and should be approached cautiously.

Penile implants

A penile prosthesis may be considered when other treatments have failed, are unsuitable or are unacceptable to the patient.

The two principal types are:

Inflatable penile prosthesis

Inflatable cylinders are placed inside the penis and connected to a pump positioned within the scrotum. Activating the pump transfers fluid into the cylinders to create a controlled erection.

Malleable penile prosthesis

Bendable rods are inserted into the penis. The penis is manually positioned for sexual activity and returned to a concealed position afterwards.

Penile implants provide a dependable erection and have high satisfaction rates among appropriately selected patients and partners. However, implantation is irreversible and carries surgical risks, including:

Infection
Bleeding
Pain
Mechanical failure
Device erosion
Injury to surrounding structures
The need for revision or replacement surgery

An implant creates rigidity but does not directly increase libido, restore penile sensation or guarantee orgasm. These functions depend on the man’s underlying health and nerve function.

The role of a men’s health physician

ED often benefits from a multidisciplinary approach involving the general practitioner, urologist, men’s health physician, endocrinologist, pelvic-floor physiotherapist or psychosexual therapist.

Dr Michael Gillman is a men’s health physician with a particular clinical interest in male sexual and reproductive health. His input may be valuable when ED occurs alongside hormonal concerns, reduced libido, ejaculation difficulties, fertility issues, complex medication factors or broader men’s health concerns. Collaboration between a men’s health physician and urologist allows medical, hormonal, psychological and surgical treatment options to be considered together.

When should you seek help?

Arrange a medical assessment if ED:

Persists or repeatedly interferes with sexual activity
Develops suddenly without an obvious explanation
Occurs with reduced libido, fatigue or other hormonal symptoms
Follows prostate or pelvic surgery
Is associated with penile pain or curvature
Is accompanied by cardiovascular risk factors
Causes anxiety, avoidance or relationship difficulties

Seek urgent medical care for an erection lasting four hours or longer. Chest pain or significant breathlessness during sexual activity also requires prompt medical assessment.

There is usually a way forward

Erectile dysfunction is common, but it should not automatically be accepted as an unavoidable part of ageing. It may provide an early warning of a broader health problem, and it can have a significant effect on both the patient and his partner.

Treatment is individualised. For some men, improving fitness, weight, sleep and cardiovascular health makes a substantial difference. Others benefit from tablets, a vacuum device, injection therapy, psychological support or a penile implant.

The most important first step is an honest conversation. If the first treatment does not work, that does not mean treatment has failed—there are several effective options to explore.

This information is general in nature and does not replace an individual medical consultation. Prescription medicines and injection therapies should only be used following assessment by an appropriately qualified healthcare professional.