Hormones . Symptoms guide
Erectile Changes: Blood Work That Matters
Quick answer
Erectile changes have many possible causes, including cardiovascular risk factors (cholesterol, blood pressure, diabetes), hormonal change (low testosterone, thyroid), nerve injury, medication side effects and psychological factors. Bloodwork covers the essential metabolic and hormonal drivers in one panel, which is a mandatory clinical safety check alongside exploring first-line treatment options. Morning, fasted appointments are required so glucose, lipids and testosterone all read against the correct baseline.
This patient information is being clinically reviewed by our team. The factual content draws on UK guidance (NHS, NICE, British Association of Dermatologists, and other specialist society guidance where cited).
What this might be
- Cardiovascular and metabolic risk. ED is often the earliest warning sign of vascular disease; cholesterol, HbA1c and fasting glucose levels provide crucial clinical context.
- Low testosterone. Less common than vascular causes but a treatable contributor.
- Thyroid dysfunction. Both under and overactive thyroid affect erection quality.
- Medication side effects. SSRIs, beta blockers, finasteride and opioids can all contribute.
When to seek urgent advice
If any of the following apply, please contact your GP or NHS 111 rather than waiting for private bloodwork.
- New onset of erectile changes accompanied by chest pain, shortness of breath, or palpitations on exertion (seek immediate emergency medical care via 999 or A&E)
- Rapid change over weeks rather than months
Common features that suggest this
- Reduced firmness or persistence of erections
- Loss of morning erections
- Concurrent fatigue, low libido, or weight gain
- Family history of heart disease or diabetes
Recommended tests
Same-day appointments at our Harley Street clinic, results clinician-reviewed.
Need a marker not in these panels? Build a custom panel and a GMC-registered clinician will design one for you.
Markers your clinician will commonly look at
These are the individual blood markers in the recommended panels above. Click any to read what it measures, its UK reference range, and what high or low values mean.
Testing advice
Morning appointment between 7:00 AM and 11:00 AM is required. Fast (water only) for 8 to 12 hours before the draw so cholesterol, fasting glucose and testosterone all read against a clean baseline. Afternoon or non-fasted samples can substantially under-read testosterone and over-read lipids and lead to a misdiagnosis.
Common questions
Is ED always hormonal?
No. In men under 40, it is more commonly psychological or medication-related, whereas over 40 it trends toward vascular drivers. Bloodwork does not diagnose psychological factors, but it rules out the hidden metabolic or hormonal issues that damage blood vessels or lower erectile capacity.
Do I need to see a urologist?
Not as a first step. In the UK, initial erectile dysfunction management (including lifestyle optimisation and first-line therapies) is handled by general practitioners or sexual medicine specialists. Bloodwork identifies whether a targeted specialist referral (such as to an endocrinologist for hormone imbalances) is required, or if the issue can be managed effectively in primary care.
Related symptoms
Sources and further reading
- NICE CKS: Erectile dysfunction
- British Society for Sexual Medicine: Guidelines on the management of erectile dysfunction
This page provides general information only and is not a substitute for medical advice. A GMC-registered clinician will review your results and tailor any recommendations to you personally.