Which blood tests are part of an ED workup?
An ED workup usually starts with four blood tests: morning total testosterone, a fasting glucose or hemoglobin A1c, a fasting lipid panel and a kidney check. The AUA erectile dysfunction guideline lists those as the basic studies, adds that thyroid tests (TSH and free T4) and PSA suit some men, and recommends a morning total testosterone for every man with ED.
| Test | What it looks for | Why it matters for erections |
|---|---|---|
| Morning total testosterone | Testosterone deficiency | Low levels can blunt desire and weaken the response to ED pills |
| A1c or fasting glucose | Prediabetes or diabetes | High sugar damages the small vessels and nerves that erections depend on |
| Fasting lipid panel | LDL, HDL, triglycerides | Cholesterol drives the artery narrowing behind most physical ED |
| Creatinine and eGFR | Kidney function | Kidney disease is linked to ED and changes how some ED medicines are cleared |
| TSH, free T4 (selected men) | Thyroid over- or underactivity | Thyroid problems can affect libido and erections |
| PSA (selected men) | Prostate health | Often paired with ED care, especially before testosterone therapy |
The NIDDK’s guide to diagnosing ED describes the same approach: a history, a physical exam that checks blood vessels, nerves and hormones, and blood tests including thyroid and prostate tests. Reference ranges vary between laboratories, so each value is read against the range on your own report.
Why can ED be an early warning for the heart?
Erections depend on small penile arteries widening on demand, and those arteries often show trouble before the larger coronary arteries do. The Princeton III consensus, written by a panel of cardiology and sexual medicine experts, describes a window of 2 to 5 years between ED onset and a coronary event, and it singles out men aged 30 to 60, in whom ED should prompt a closer look at heart risk. The AUA guideline puts it more simply: ED symptoms may come before a cardiovascular event by up to five years.
A large U.S. study makes the point with numbers. Among 9,457 men aged 55 and older in the placebo group of the Prostate Cancer Prevention Trial, men with ED had a 45% higher risk of later cardiovascular events (hazard ratio 1.45) after adjustment for other risk factors. The authors noted that this was in the range of risk tied to current smoking or a family history of heart attack.
Our page on ED as an early sign of heart disease covers the cardiac side in more depth.
Why do the glucose and lipid results matter as much as testosterone?
Because most physical ED is a blood-flow problem, the sugar and cholesterol numbers often explain more than the hormone result does. Testosterone tells you about desire and how well ED medicines can work. A1c and lipids tell you about the arteries, and those arteries supply your heart and brain as well.
MedlinePlus lists an A1c below 5.7% as normal, 5.7% to 6.4% as prediabetes and 6.5% or higher as diabetes. For men aged 20 and older, MedlinePlus gives a healthy LDL as under 100 mg/dL and calls HDL under 40 mg/dL low. The AUA guideline notes that up to 42.4% of men with ED also have high cholesterol.
A man whose ED leads to a first diagnosis of prediabetes has gained something far bigger than an erection answer. Our HbA1c test for men and lipid panel for men pages explain each result, and the page on ED with diabetes covers how blood sugar damages erectile tissue.
How is testosterone measured in an ED workup?
Testosterone is checked in the morning, and a low first result is repeated before anyone calls it deficiency. The AUA defines testosterone deficiency as a total below 300 ng/dL with symptoms and signs, confirmed on at least two morning draws, because afternoon values in young men can run about 20% lower than morning ones.
The result changes treatment in a specific way. The AUA guideline notes that in men with both ED and testosterone deficiency, ED pills may work better when testosterone is also treated. A normal testosterone, on the other hand, points the search back toward blood flow, nerves, medicines or stress. If low desire is the bigger complaint than erection quality, our page on blood tests for low libido in men explains why prolactin and estradiol join the panel.
What blood tests cannot tell you
Blood work finds causes and risks, but it does not measure the erection itself. A normal panel does not prove a problem is psychological, and an abnormal one does not prove the lab value is the only cause. When the picture is unclear, specialists use other tools, such as a nighttime erection test or an ultrasound of penile blood flow, described in our answer on tests used to diagnose ED.
Some symptoms need emergency care rather than a lab appointment. Chest pain, pressure or shortness of breath during or after sex means calling 911. An erection lasting more than four hours is a medical emergency: go to the nearest emergency room.
How Ultimate Male runs ED blood work
ED care at Ultimate Male starts with labs, not a pill. Your provider reviews your medicines and history, then decides which markers you need. For many men, the Comprehensive Health Optimization Panel covers the full workup in one draw: total and free testosterone, SHBG, estradiol, prolactin, TSH and free T4, a lipid panel with ApoB and lipoprotein(a), hs-CRP, HbA1c and a comprehensive metabolic panel for kidney and liver function.
Blood is drawn on site the same day at San Gabriel or Downey, and results are typically back in 24 to 48 hours. A one-on-one consultation with a PA-C or MD then connects the numbers to your symptoms and to the erectile dysfunction treatment options that fit, from oral medicines to injectables. If a result points to heart risk, you leave with that flagged clearly and a plan to address it, including coordination with your primary care doctor.
