Blood tests for low libido in men: what to check besides testosterone
Besides testosterone, the blood tests most worth discussing for low libido in men are prolactin and thyroid tests, plus blood sugar (HbA1c or fasting glucose) and cholesterol if erections are also affected. Medications, mood and sleep matter just as much, and no blood test shows them.
European urology guidelines strongly recommend lab tests for hormone causes in men with low desire, naming testosterone, prolactin and thyroid hormones. Numia Health, a physician-ordered, at-home blood testing service in Greater Vancouver, covers testosterone and thyroid hormones; your doctor can order prolactin.
Why start with testosterone?
Because low testosterone is tied to low desire. In a European study of 3,369 men aged 40 to 79, low desire, poor morning erections and erectile dysfunction were the sexual symptoms linked to lower testosterone (Wu et al., 2010).
Test in the morning, when testosterone peaks (why timing matters). Numia's Male Hormone Panel adds SHBG, the protein that carries testosterone, plus free testosterone and LH (the brain's signal), so a borderline total can be read in context and kept as a baseline.
Which other blood tests help explain low libido?
| Test | Why it's checked | At Numia |
|---|---|---|
| Prolactin | High levels lower libido and can cause erection problems | Not on men's panels |
| TSH | Thyroid disease shifts SHBG and can lower testosterone | Thyroid Basic, Fatigue, Weight Loss Monitoring |
| HbA1c or fasting glucose; lipids | Canada's erectile dysfunction guideline uses them to find hidden diabetes and high cholesterol | Fatigue (blood sugar); Weight Loss Monitoring (both) |
Erection problems deserve a physician's attention too. In 9,457 US men aged 55 and older, new erectile dysfunction went with a 25% higher rate of later heart and blood vessel events, after adjusting for other risk factors (Thompson et al., 2005).
Which medications and habits lower sex drive?
- Antidepressants. Decreased sex drive is a listed side effect of sertraline, a common antidepressant.
- Finasteride. Decreased sexual desire is a listed side effect, yet BC's protocol says it can raise testosterone, so a normal result doesn't rule it out.
- Opioids and spironolactone can lower testosterone; with opioids, long-term use is the concern.
- Alcohol, cannabis, obesity and some sleep disorders are on BC's list of causes of low testosterone.
Don't stop or change a medication on your own; any change is your prescriber's decision. If you book with Numia, list your medications at intake.
Where does Numia fit?
The usual route runs in steps: an appointment, a lab visit, a wait, then another appointment for results, publicly funded when clinically indicated. LifeLabs' BC online store skips the first appointment for a standalone testosterone test, with a downloadable Patient Guidebook, though you still visit a lab.
Numia brings the steps together. A licensed Canadian physician approves your requisition online in about three minutes, and a clinician comes to your home for a 10-minute morning draw. The Male Hormone Panel measures total and free testosterone, SHBG, albumin, LH and DHEAS, with plain-English results in the Numia app in 7 days. An optional wellness consultation is available. Numia is an HSA-eligible service that sells testing, not treatment.
Frequently asked questions
What blood tests should men get for low libido besides testosterone?
Usually prolactin and TSH, plus HbA1c or fasting glucose and lipids if erections are affected, and LH when testosterone is low. Numia's panels cover all but prolactin.
What hormone problems cause low sex drive in men?
Low testosterone, high prolactin and thyroid disease are the ones guidelines name. A persistently high prolactin needs a physician's follow-up to rule out a pituitary tumour (prolactinoma). Numia's Male Hormone Panel covers testosterone.
Is low libido with normal testosterone worth checking further?
Yes. Canada's testosterone guideline advises ruling out depression, an underactive thyroid and sleep disorders. SHBG and calculated free testosterone can clarify a borderline total (levels by age); Numia reports both.
Sources16 references
- Domes, T., Najafabadi, B. T., Roberts, M., Campbell, J., Flannigan, R., Bach, P., Patel, P., Langille, G., Krakowsky, Y., & Violette, P. D. (2021). Canadian Urological Association guideline: Erectile dysfunction. Canadian Urological Association Journal, 15(10), 310–322. View source
- European Association of Urology. (2026). Low sexual desire and male hypoactive sexual desire disorder. In EAU guidelines on sexual and reproductive health. Retrieved September 22, 2026, from View source
- Grober, E. D., Krakowsky, Y., Khera, M., Holmes, D. T., Lee, J. C., Grantmyre, J. E., Patel, P., Bebb, R. A., Fitzpatrick, R., Campbell, J. D., Carrier, S., & Morgentaler, A. (2021). Canadian Urological Association guideline on testosterone deficiency in men: Evidence-based Q&A. Canadian Urological Association Journal, 15(5), E234–E243. View source
- Grover, S. A., Lowensteyn, I., Kaouache, M., Marchand, S., Coupal, L., DeCarolis, E., Zoccoli, J., & Defoy, I. (2006). The prevalence of erectile dysfunction in the primary care setting: Importance of risk factors for diabetes and vascular disease. Archives of Internal Medicine, 166(2), 213–219. View source
- Guidelines and Protocols Advisory Committee. (2022). Testosterone testing protocol (revised October 27, 2022). BC Guidelines. British Columbia Ministry of Health. View source
- LifeLabs. (n.d.). Testosterone lab test [LifeLabs Store, British Columbia]. Retrieved September 23, 2026, from View source
- MedlinePlus. (2025). Sertraline. National Library of Medicine. View source
- MedlinePlus. (2026). Finasteride. National Library of Medicine. View source
- Melmed, S., Casanueva, F. F., Hoffman, A. R., Kleinberg, D. L., Montori, V. M., Schlechte, J. A., & Wass, J. A. H. (2011). Diagnosis and treatment of hyperprolactinemia: An Endocrine Society clinical practice guideline. The Journal of Clinical Endocrinology & Metabolism, 96(2), 273–288. View source
- Numia Health. (n.d.). Fatigue Panel. Retrieved September 24, 2026, from View source
- Numia Health. (n.d.). Female Hormone Pre-Menopause Panel. Retrieved September 25, 2026, from View source
- Numia Health. (n.d.). Male Hormone Panel. Retrieved September 25, 2026, from View source
- Numia Health. (n.d.). Thyroid Basic Panel. Retrieved September 24, 2026, from View source
- Numia Health. (n.d.). Weight Loss Monitoring. Retrieved September 25, 2026, from View source
- Thompson, I. M., Tangen, C. M., Goodman, P. J., Probstfield, J. L., Moinpour, C. M., & Coltman, C. A. (2005). Erectile dysfunction and subsequent cardiovascular disease. JAMA, 294(23), 2996–3002. View source
- Wu, F. C. W., Tajar, A., Beynon, J. M., Pye, S. R., Silman, A. J., Finn, J. D., O'Neill, T. W., Bartfai, G., Casanueva, F. F., Forti, G., Giwercman, A., Han, T. S., Kula, K., Lean, M. E., Pendleton, N., Punab, M., Boonen, S., Vanderschueren, D., Labrie, F., Huhtaniemi, I. T., & EMAS Group. (2010). Identification of late-onset hypogonadism in middle-aged and elderly men. The New England Journal of Medicine, 363(2), 123–135. View source
Last updated November 3, 2026
