Sexual health · Condition guide

Erectile dysfunction

Difficulty getting or keeping an erection is common, has a cause that can usually be found, and is treatable in most men.

Written and medically reviewed by Dr Shivadev M, MBBS, MD (Psychiatry), FECSMLast reviewed November 2026

What erectile dysfunction is

Erectile dysfunction (ED) means difficulty getting or keeping an erection firm enough for satisfying sex, happening repeatedly over several months.¹ An occasional bad night, after alcohol, exhaustion or a stressful day, is not ED.

It is far more common than most men think. In one large study, about half of men aged 40 to 70 reported some degree of erectile difficulty.² It also happens in younger men, where anxiety often plays a bigger part.

What causes it

An erection needs healthy blood vessels, working nerves, normal hormones, and a mind that isn't under threat. A problem in any of these can cause ED, and most men have more than one factor.

Blood vessels. Diabetes, high blood pressure, high cholesterol, smoking and excess weight damage small arteries. The penile arteries are narrow, so the damage often shows there first.
Hormones. Low testosterone, thyroid problems or a raised prolactin level.
Nerves. Diabetes, spinal problems, and pelvic surgery or radiotherapy, including for prostate or bowel cancer.
Medicines. Some medicines for blood pressure, depression, anxiety, prostate enlargement and hair loss.
Mind and relationship. Performance anxiety, depression, stress and relationship strain. Once an erection has failed, worry about it happening again can keep the problem going even after the original cause has passed.
Alcohol, tobacco and other substances.

Why it matters for your heart

ED and heart disease share the same underlying process in the blood vessels. Erectile difficulty often appears a few years before heart symptoms, so it can be an early warning.^3,4 International guidance recommends that every man with ED of a likely physical cause has his cardiovascular risk assessed.³

I've written more about this in Erectile dysfunction can be an early warning for your heart.

How I assess it

A detailed history. When it started, whether it is sudden or gradual, whether morning or self-stimulated erections still happen, desire, ejaculation, mood, stress and the relationship.
A validated questionnaire, the IIEF-5, which gives a score we can track over time.⁵
A physical examination, including blood pressure, weight and waist measurement.
Blood tests where indicated: fasting sugar and HbA1c, cholesterol, and morning testosterone; thyroid and prolactin when the history suggests them.^6,7
Further tests such as a penile Doppler ultrasound, only when the result would change treatment.

Treatment

Treatment is chosen after the assessment, and usually combines more than one approach.

Treating the cause and the risk factors. Better control of sugar and blood pressure, stopping smoking, losing weight and regular exercise improve erections and protect the heart.⁶
Reviewing medicines. If a medicine is likely to blame, there is often an alternative. Please don't stop any medicine on your own.
Oral medicines (PDE5 inhibitors). These help most men with ED. They need sexual stimulation to work, and must never be taken with nitrate medicines for chest pain.^6,7
Psychosexual therapy. Structured work on performance anxiety, often with your partner. This is especially useful when anxiety is keeping the problem going, and it helps medicines work better.
Hormone treatment, only when testosterone is confirmed to be low on repeat testing and there are matching symptoms.
Other options when tablets don't work or aren't suitable: vacuum devices, injection therapy, and in a small number of men, referral for surgery.⁶

When to see a doctor

See a doctor if erections have been unreliable for more than a few months, if the change is new and you are under 50, if you have diabetes or heart risk factors, or if it is affecting your confidence or relationship. Seek urgent help for an erection lasting more than four hours, or for chest pain or breathlessness during sex.

Common questions

Is erectile dysfunction always physical?

No. In younger men anxiety is often the main factor, and in older men there is usually a physical cause too. Many men have both, which is why the assessment covers mind and body together.

Can erectile dysfunction be cured?

Often, yes, when the cause can be treated: performance anxiety, a medicine side effect, low testosterone, or lifestyle factors. When the cause is long-standing blood-vessel disease, ED can usually be well controlled even if it isn't fully reversed.

Are ED tablets safe?

For most men they are, after an assessment. They are dangerous with nitrate medicines for chest pain and need care with some other heart and blood pressure medicines. Tablets bought online without a prescription may also contain undeclared ingredients.

Should my partner come to the consultation?

It's up to you. Many men come alone first. A partner's involvement often helps, especially when anxiety or the relationship is part of the problem.

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Related guides

References

NIH Consensus Development Panel on Impotence. Impotence. JAMA. 1993;270(1):83–90.
Feldman HA, Goldstein I, Hatzichristou DG, et al. Impotence and its medical and psychosocial correlates: results of the Massachusetts Male Aging Study. J Urol. 1994;151(1):54–61.
Nehra A, Jackson G, Miner M, et al. The Princeton III Consensus recommendations for the management of erectile dysfunction and cardiovascular disease. Mayo Clin Proc. 2012;87(8):766–778.
Thompson IM, Tangen CM, Goodman PJ, et al. Erectile dysfunction and subsequent cardiovascular disease. JAMA. 2005;294(23):2996–3002.
Rosen RC, Cappelleri JC, Smith MD, et al. Development and evaluation of an abridged, 5-item version of the International Index of Erectile Function (IIEF-5). Int J Impot Res. 1999;11(6):319–326.
European Association of Urology. EAU Guidelines on Sexual and Reproductive Health. Updated annually.
Burnett AL, Nehra A, Breau RH, et al. Erectile dysfunction: AUA guideline. J Urol. 2018;200(3):633–641.

This page is general information and does not replace a consultation with a doctor who has assessed you. Read how these pages are written in our editorial policy.