Hyperbaric oxygen therapy (HBOT) involves breathing pure oxygen in a pressurised chamber and is used in the NHS for specific conditions such as decompression sickness and carbon monoxide poisoning. Some private clinics suggest HBOT may help erectile dysfunction by improving blood flow to penile tissues, but does hyperbaric oxygen therapy help erectile dysfunction in practice? Currently, HBOT is not a NICE-endorsed or NHS-commissioned treatment for erectile dysfunction, and evidence supporting its use for this indication remains limited and investigational. Men experiencing erectile dysfunction should consult their GP to access proven treatments and investigate potential underlying cardiovascular or metabolic conditions.

What Is Hyperbaric Oxygen Therapy and How Does It Work?

Hyperbaric oxygen therapy (HBOT) is a medical treatment in which patients breathe 100% oxygen whilst inside a pressurised chamber. The atmospheric pressure inside the chamber is typically increased to between 1.5 and 3 times normal sea-level pressure. This combination of high oxygen concentration and increased pressure allows significantly more oxygen to dissolve in the blood plasma and be delivered to body tissues.

The mechanism of action centres on enhanced oxygen delivery to areas with compromised blood flow. Under normal conditions, oxygen is primarily carried by haemoglobin in red blood cells. However, under hyperbaric conditions, the increased pressure forces additional oxygen to dissolve directly into plasma, cerebrospinal fluid, and lymph. This can temporarily improve oxygen supply to tissues that may be oxygen-starved due to damaged or narrowed blood vessels.

In the UK, HBOT is commissioned by NHS England for a limited number of specific indications, including decompression sickness (the bends), carbon monoxide poisoning, gas gangrene, and certain other acute conditions. Medical oxygen used in HBOT is a licensed medicinal product regulated by the Medicines and Healthcare products Regulatory Agency (MHRA), and facilities providing HBOT must meet healthcare and medical device standards. Treatment regimens vary by indication: sessions typically last 60–90 minutes, and the number and frequency of sessions depend on the condition being treated.

Some researchers have theorised that HBOT might improve erectile dysfunction by promoting blood vessel repair and new vessel formation (angiogenesis), potentially improving penile blood flow. However, this rationale remains speculative and is supported only by small, preliminary studies. It is important to note that HBOT is not currently a recognised or NICE-endorsed treatment for erectile dysfunction in the UK, is not included in NHS commissioning policies for this indication, and evidence supporting its use for ED remains limited and investigational. Men considering HBOT for erectile dysfunction should be aware that it is not part of standard NHS care pathways for this condition.

Understanding Erectile Dysfunction: Causes and Risk Factors

Erectile dysfunction (ED) is defined as the persistent inability to achieve or maintain an erection sufficient for satisfactory sexual performance. It is a common condition in the UK, with prevalence increasing significantly with age. Estimates vary, but ED affects a substantial proportion of men over 40, with rates rising further in older age groups.

The underlying causes of ED are multifactorial and can be broadly categorised into vascular, neurological, hormonal, and psychological factors. Vascular causes are the most common, as achieving an erection requires adequate blood flow to the penile tissues. Conditions that damage blood vessels—such as cardiovascular disease, hypertension, diabetes mellitus, and hyperlipidaemia—are major risk factors. Atherosclerosis (narrowing of arteries) can reduce blood flow to the penis, just as it affects coronary and peripheral vessels.

Neurological conditions including multiple sclerosis, Parkinson's disease, spinal cord injury, and pelvic surgery (particularly radical prostatectomy) can disrupt the nerve signals necessary for erection. Hormonal imbalances, most notably low testosterone (hypogonadism), can also contribute to ED, though this accounts for a smaller proportion of cases.

Lifestyle and psychological factors play significant roles. Smoking, excessive alcohol consumption, obesity, and physical inactivity all increase ED risk. Medications including certain antihypertensives, antidepressants, antipsychotics, 5-alpha-reductase inhibitors, antiandrogens, and opioids may cause or worsen erectile problems. Psychological factors such as anxiety, depression, relationship difficulties, and stress can either cause ED directly or exacerbate physical causes.

Importantly, ED can be an early warning sign of cardiovascular disease, as the penile arteries are smaller than coronary arteries and may show atherosclerotic changes earlier. Men presenting with ED should therefore undergo formal cardiovascular risk assessment (for example, using QRISK) as part of their initial evaluation.

Evidence-Based Treatments for Erectile Dysfunction in the UK

NICE Clinical Knowledge Summary (CKS) for erectile dysfunction recommends a stepwise approach to management, beginning with lifestyle modification and progressing to pharmacological and, if necessary, specialist interventions. The first-line approach involves addressing modifiable risk factors: smoking cessation, reducing alcohol intake, increasing physical activity, achieving healthy weight, and optimising management of underlying conditions such as diabetes and hypertension.

Phosphodiesterase type 5 (PDE5) inhibitors represent the first-line pharmacological treatment for ED in the UK. These include sildenafil, tadalafil, vardenafil, and avanafil. These medications work by enhancing the effects of nitric oxide, a natural chemical that relaxes smooth muscle in the penis and increases blood flow during sexual stimulation. Sexual stimulation is required for these medicines to be effective. They are typically taken orally 30–60 minutes before sexual activity (on-demand regimen), though tadalafil can also be taken daily at a lower dose for continuous effect.

Common adverse effects include headache, facial flushing, dyspepsia, nasal congestion, and visual disturbances. Important contraindications and interactions include: PDE5 inhibitors must not be used with nitrates or nicorandil due to risk of severe hypotension; they are contraindicated with riociguat (a guanylate cyclase stimulator); and caution is required when co-prescribed with alpha-blockers due to additive blood pressure-lowering effects. Men should be advised to report any suspected adverse reactions via the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk or the Yellow Card app).

For men who cannot use or do not respond to optimised first-line PDE5 inhibitor therapy, second-line treatments include intracavernosal injections (alprostadil), intraurethral alprostadil, or vacuum erection devices. These mechanical and pharmacological options can be effective but require proper training and patient motivation. Testosterone replacement therapy may be appropriate for men with confirmed hypogonadism, though this should only be initiated after specialist assessment and repeat confirmatory testing.

Psychological interventions, including cognitive behavioural therapy (CBT) and psychosexual counselling, are recommended either alone (for primarily psychological ED) or alongside medical treatments. Referral to specialist services (urology or sexual medicine) should be considered for men with inadequate response to first-line therapy, suspected anatomical abnormalities (such as Peyronie's disease), confirmed or suspected endocrine disorders, or complex comorbidity. For refractory cases, surgical options such as penile prosthesis implantation may be considered following specialist urology assessment.

Regarding hyperbaric oxygen therapy, HBOT is not included in NICE CKS, British Society for Sexual Medicine guidance, or NHS care pathways for erectile dysfunction. It remains an experimental approach not routinely available through the NHS for this indication, and men should be cautious about private clinics offering HBOT for ED outside of research protocols.

Safety Considerations and When to Seek Medical Advice

Men experiencing erectile dysfunction should consult their GP rather than seeking unproven treatments. ED can be an important indicator of underlying cardiovascular disease, and early medical assessment allows for appropriate investigation and risk factor management. A GP consultation typically involves a detailed medical and sexual history, medication review, and physical examination.

Initial investigations usually include blood tests to assess:

• HbA1c (to screen for diabetes)

• Lipid profile (to assess cardiovascular risk)

• Morning (around 9 am) serum total testosterone on two separate occasions if initial result is low or symptoms suggest hypogonadism

• Thyroid function tests and prolactin if clinically indicated

Formal cardiovascular risk assessment (for example, using QRISK) should be undertaken, given the association between ED and cardiovascular disease.

Regarding hyperbaric oxygen therapy specifically, whilst generally safe when administered in regulated medical facilities for NHS-commissioned indications, it is not without risks. Potential adverse effects include:

• Barotrauma to the ears, sinuses, or lungs due to pressure changes

• Oxygen toxicity, which can cause seizures if exposure is prolonged

• Temporary myopia (short-sightedness) lasting several weeks

• Claustrophobia in the confined chamber environment

• Fire risk due to the oxygen-rich environment

Absolute contraindications to HBOT include untreated pneumothorax. Relative contraindications include severe COPD with bullae or air-trapping, recent ear surgery, current upper respiratory infections, and certain prior chemotherapy agents (such as bleomycin). There is currently insufficient evidence to recommend HBOT for erectile dysfunction, and men should be cautious about private clinics offering this treatment for ED outside of research protocols.

Seek urgent medical advice if you experience:

• Sudden onset ED, particularly if accompanied by chest pain, as this may indicate acute cardiovascular disease and requires emergency assessment

• Priapism (painful erection lasting more than 4 hours), which can occur with some ED treatments and requires emergency medical attention to prevent permanent damage

• Any neurological symptoms (such as weakness, sensory changes, or bowel/bladder disturbance) alongside ED, which may indicate serious underlying pathology

Men should discuss all treatment options, including their risks and benefits, with their GP or a specialist in sexual medicine or urology. The NHS provides access to evidence-based treatments for ED, and self-treatment with unproven therapies may delay appropriate diagnosis and management of both the erectile dysfunction and any underlying health conditions. If you experience any suspected side effects from medicines or medical devices, report them via the MHRA Yellow Card scheme at yellowcard.mhra.gov.uk or using the Yellow Card app.

Frequently Asked Questions