At a glance
- ED has four main groups of causes: diseases and conditions, medicines, mental or emotional issues and lifestyle – often more than one at once.
- The most common medical causes involve blood vessels, nerves or hormones – diabetes, heart and blood vessel disease, low testosterone, nerve damage.
- ED may be a symptom of another health problem, which is the main reason to have it checked.
- Many everyday medicines can cause ED – but never stop one on your own.
- Lifestyle causes – smoking, alcohol, inactivity, drugs – are the ones you can change directly.
Symptoms of ED
ED means regularly being unable to get or keep an erection firm enough for sex. A self-check and an explanation of how doctors diagnose it are in do I have ED?.
Diseases and conditions
| Group | Examples |
|---|---|
| Diabetes | Type 1 and type 2 diabetes |
| Heart and blood vessel diseases | Atherosclerosis, high blood pressure, stroke |
| Chronic conditions | Chronic kidney disease, obesity and overweight, COPD |
| Hormone issues | Low testosterone, thyroid imbalance |
| Nerve damage or disorders | Multiple sclerosis, spinal cord injury, damage from pelvic surgery |
| Male reproductive system | Enlarged prostate, penile curvature (Peyronie’s disease) |
NIDDK groups these as conditions that affect blood vessels, nerves or hormones. The cause also influences how well treatment works: in Viagra’s trials, 57% of men with diabetes and 43% after radical prostate surgery improved, compared with 74–82% at the usual doses in the general ED population.[1][3]
Medicines that can cause ED
| Medicine group | Examples or use |
|---|---|
| Antidepressants | Used for depression and anxiety |
| Appetite suppressants | Medicines that reduce hunger |
| Antihistamines | For allergies or heartburn |
| Blood-pressure medicines and diuretics | Including water pills |
| Chemotherapy and hormone medicines | Cancer and hormone treatments |
| Some pain relievers | NSAIDs, codeine, oxycodone |
| Sedatives | Medicines that calm or make you sleepy |
| Ulcer medicines | For stomach or duodenal ulcers |
All examples from NIDDK. If you suspect a medicine, talk to your clinician – they may change the dose or switch to another medicine. Do not stop taking a medicine on your own.[1][2]
Mental and emotional causes
Anxiety, depression or stress; feeling isolated or lonely; and low self-esteem, lack of confidence or negative body image can either cause ED or make it worse. Counseling – sometimes together with a partner – can help lower anxiety and stress about sex. See supporting a partner with ED.[1][2]
Lifestyle
| Behavior | What helps |
|---|---|
| Not enough physical activity | At least 150 minutes of moderate activity a week |
| Drinking too much alcohol | Limit or stop alcohol |
| Smoking | Quit – smoking is linked to heart and blood vessel disease |
| Recreational and illicit drugs | Stop – they can prevent arousal and mask other causes |
Causes from NIDDK’s symptoms page; recommendations from its prevention guidance.[1][2]
Why ED can be a warning sign
Because many causes are conditions such as diabetes, high blood pressure or atherosclerosis, NIDDK notes that ED may be a symptom of another health problem.[1] Having ED checked can therefore lead to finding and treating a condition that matters well beyond sex.
What to do next
- See a clinician: they treat the underlying cause when possible and review your medicines.[2]
- Make the lifestyle changes you can.[2]
- Ask about treatment options – see all ED treatment options and natural ways to deal with ED.
- Read the overview of erectile dysfunction.
Questions people ask
What is the most common cause of ED?
Can ED be caused by stress alone?
Can my medicines cause ED?
Is ED a sign of heart disease?
Does alcohol cause ED?
Can young men get ED?
Does ED get better if the cause is treated?
Conclusion: what we know, what we don’t, and what follows
What we know today
Established
- ED has well-documented causes in four groups – diseases and conditions affecting blood vessels, nerves or hormones; many common medicines; mental and emotional issues; and lifestyle behaviors.[1]
- ED may be a symptom of another health problem, such as diabetes or heart and blood vessel disease.[1]
- The underlying cause affects how well treatment works – for example, response to sildenafil is lower in men with diabetes or after prostate surgery.[3]
What we don’t know yet
- In an individual man, how much each factor contributes is often impossible to separate; several causes frequently act together.
- Sometimes the exact cause of ED is not known, and treatment then focuses on improving sexual function.[2]
Bottom line
Erectile dysfunction is rarely just about erections. Its most common causes are conditions of the blood vessels, nerves and hormones, everyday medicines, emotional strain and habits – and the same problem that limits sex may be affecting the heart or metabolism. That is why the most useful first step is not a pill but a check-up: finding the cause tells you what can be changed, what can be treated, and which treatment is most likely to work.
Sources
- NIDDK: Symptoms & Causes of Erectile Dysfunction (last reviewed October 2024)
- NIDDK: Treatment for Erectile Dysfunction (last reviewed October 2024)
- FDA: VIAGRA (sildenafil citrate) prescribing information, 2017 (PDF)
Sources checked October 11, 2026.
