Signs of Erectile Dysfunction: How to Know If You Have ED

Symptoms, diagnostic criteria, what is and isn't ED, and what to do next.

Part of the Access Doctor Erectile Dysfunction guide.

What Is and Isn't Erectile Dysfunction

Occasional difficulty achieving or maintaining an erection is entirely normal. Stress, tiredness, alcohol, illness, and relationship tension can all cause temporary difficulties that resolve without any intervention. These isolated incidents are not erectile dysfunction.

ED becomes a clinical concern when:

• It occurs more than half the time when you attempt sexual activity
• It has been consistently present for more than 2–4 weeks
• It is causing significant distress, anxiety, or affecting your relationships or quality of life
• It is accompanied by other symptoms suggesting an underlying health condition (reduced libido, unexplained fatigue, weight change)

Signs and Symptoms of Erectile Dysfunction

Primary erectile symptoms

• Inability to achieve an erection despite sexual stimulation — the penis does not become erect at all
• Insufficient firmness — an erection develops but is not firm enough for penetration
• Loss of erection before or during sexual activity — the erection subsides before or immediately after penetration

Associated symptoms

• Reduced sexual desire (low libido) — often associated with hormonal causes (low testosterone, thyroid disorders)
• Changes in ejaculation — premature or delayed ejaculation can co-occur with ED, particularly in anxiety-driven cases
• Anxiety and avoidance — actively avoiding sexual situations due to fear of failure; both a symptom and a maintaining factor
• Relationship strain — conflict, withdrawal, or communication difficulties around intimacy

ED vs Other Conditions

Reduced libido

A reduction in sexual desire is distinct from ED. A man with low libido may not initiate sexual activity or feel arousal, but when arousal does occur erections may still function normally. A man with ED typically has normal desire but struggles with the physical erection response. Both can occur together — particularly when hormonal causes or depression are involved.

Ejaculation problems

Premature ejaculation (PE) and ED are different conditions. However, performance anxiety can cause both simultaneously: a man anxious about losing his erection may rush to ejaculate, creating a co-presentation of anxiety, ED, and PE.

Nocturnal and morning erections

Healthy men typically have 3–5 nocturnal erections during sleep. If you consistently have morning erections despite experiencing ED during partnered sex, this suggests the physical mechanism is intact and a psychological cause — most likely performance anxiety — is the dominant factor. Absent morning and nocturnal erections point toward a physical cause.

What Causes ED?

ED can arise from physical causes (cardiovascular disease, diabetes, hypertension, hormonal conditions, nerve damage), psychological causes (anxiety, depression, stress, relationship difficulties), or medication side effects — most commonly a combination that interacts and reinforces itself. For a full breakdown, see what causes erectile dysfunction.

How Is Erectile Dysfunction Diagnosed?

Clinical history

A prescriber or GP will ask about the nature, onset, frequency and severity of your symptoms; your general health and cardiovascular risk factors; current medications; and lifestyle. A validated questionnaire — the International Index of Erectile Function (IIEF) — may be used to assess symptom severity.

Blood tests

• Testosterone (morning sample — levels follow a circadian rhythm)
• Fasting blood glucose or HbA1c (diabetes screening)
• Lipid profile (cholesterol)
• Thyroid function tests
• Full blood count

Blood pressure

Blood pressure assessment is standard in ED evaluation — hypertension is a significant contributing cause and relevant to prescribing decisions.

When to Seek Help

Seek assessment if ED has been consistently present for more than 2–4 weeks, is causing distress or affecting your quality of life, you have underlying health conditions (diabetes, high blood pressure, heart disease), ED began after starting a new medication, or you are under 40 (a thorough assessment is particularly important in younger men, where ED can be an early indicator of underlying cardiovascular or metabolic disease).