Low Testosterone Symptoms in Men Over 40: What to Test First
Men's Health
Low testosterone symptoms in men over 40: what to test first.
Tired, flat, less interested in sex, softer around the middle. Before anyone hands you a prescription, the right labs come first, drawn the right way.
He sits down, arms crossed, and tells me his wife made the appointment. He is 46. He sleeps badly, falls asleep on the couch by nine, has stopped going to the gym, and after a long pause admits the bedroom has gone quiet too. He has already decided it is low testosterone.
Maybe. But low testosterone symptoms in men over 40 look a lot like poor sleep, sleep apnea, depression, thyroid trouble, and insulin resistance. The order of testing matters as much as the test itself.
The low testosterone symptoms that actually point to it
Symptoms do not all carry the same weight. A large European study of more than 3,000 men aged 40 to 79 found that three sexual symptoms tracked most closely with low levels: fewer morning erections, lower sex drive, and erectile dysfunction. Fatigue, low mood, and trouble with vigorous activity were linked too, but less specifically.
- Fewer or weaker morning erections
- Lower desire than your own normal
- Erections that are harder to get or keep
- Fatigue and less drive, even after decent sleep
- Losing muscle while gaining fat around the middle
- Low mood, irritability, a shorter fuse
One symptom proves very little. Three or more, especially the sexual ones, is a reason to test.
What to test first, and how to draw it
This is where a lot of men get misread. Testosterone runs highest in the morning and drops through the day. In one study, men in their 30s and 40s had afternoon levels 20 to 25 percent lower than at 8 AM, and some men who tested low after noon were normal every single morning.
So the Endocrine Society and the American Urological Association ask for the same starting point: a fasting, early morning total testosterone, repeated on a second day before anyone calls it low.
Total testosterone, twice
Morning, fasting, accurate assay. One low number is a question. Two is a pattern.
Free testosterone and SHBG
Needed when total sits near the bottom of the range, or when weight, age, or thyroid status may be shifting the binding protein. Our post on free vs total testosterone explains why.
LH and FSH
These show whether the testes are not responding or the brain is not sending the signal. That changes the workup and the treatment conversation.
The safety baseline
A blood count with hematocrit, estradiol, and a PSA when age and history call for it. These are the numbers we watch if treatment ever starts, so we need them before it does.
The look-alikes
A thyroid panel, A1c and fasting insulin, lipids, ferritin, and vitamin D. Any of these can produce the same tired, flat picture.
Skip the brutal late workout and the heavy drinking the night before your draw. Both can push a morning result down, and you want a number that reflects your normal week, not your worst one.
The conditions that mimic it
Sleep apnea is the big one. Snoring, waking unrefreshed, a thick neck, and daytime sleepiness should be screened before testosterone becomes the explanation. Extra weight around the middle lowers testosterone on its own, and so does uncontrolled blood sugar. Heavy drinking, chronic stress, and some medications pile on.
So ask yourself two honest questions before your labs: how many hours do you actually sleep, and how much do you drink in a normal week? Those two answers change more results than men expect.
And sometimes testosterone really is low because of something else entirely: a pituitary problem, an old injury, a genetic condition. That is why LH and FSH are not optional.
Low testosterone means symptoms plus consistently low morning labs. Either one alone is not enough to start treatment, and a good clinician will tell you so.
What happens after the labs
If your labs come back normal, that is useful. We stop guessing and look harder at sleep, metabolic health, and mood. If they confirm a low level, we talk through the cause, your options, your fertility plans, and the risks before anything is prescribed. Men who want children soon need a different plan, and that conversation happens first.
Treatment, when it fits, is a long-term commitment with regular rechecks of hematocrit, PSA, and how you feel. I would rather spend one extra visit confirming the diagnosis than spend years treating the wrong problem.
At Navara, men's hormone consults are virtual. Testosterone care is Texas only and requires one in-person visit at our Dallas clinic. Baseline labs are required before any hormone treatment. No exceptions.
Common questions
Can I get my testosterone checked at any time of day?
You can, but an afternoon result can read falsely low. Draw it fasting, early in the morning, and repeat it on a second day before anyone calls it low.
Do I need free testosterone too?
Often, yes. If your total is near the low end, or weight, age, or thyroid status may be affecting the binding protein SHBG, free testosterone gives a truer read.
Is low testosterone a normal part of turning 40?
Levels drift down with age, but symptoms plus consistently low labs are a medical finding, not a personality change. They deserve a real workup.
Morning labs drawn the right way, a real review, and a plan built on what the numbers show.
Book a Start VisitThis article is general education, not medical advice for any individual. Talk with your own clinician about what fits your history.
Written and clinically reviewed by Jessica Boggs, MSN, APRN, FNP-C, ENP-C, founder of Navara Health. Medical oversight by Simal Patel, MD.
Last reviewed November 2, 2026. This page is general information, not medical advice, and does not create a provider relationship.
Sources
- Bhasin S, Brito JP, Cunningham GR, et al. Testosterone therapy in men with hypogonadism: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab. 2018;103(5):1715-1744.
- Mulhall JP, Trost LW, Brannigan RE, et al. Evaluation and management of testosterone deficiency: AUA guideline. J Urol. 2018;200(2):423-432.
- Wu FC, Tajar A, Beynon JM, et al. Identification of late-onset hypogonadism in middle-aged and elderly men. N Engl J Med. 2010;363(2):123-135.
- Brambilla DJ, Matsumoto AM, Araujo AB, McKinlay JB. The effect of diurnal variation on clinical measurement of serum testosterone and other sex hormone levels in men. J Clin Endocrinol Metab. 2009;94(3):907-913.