Blood tests on testosterone therapy

For men and anyone else taking testosterone prescribed for low testosterone, as injections, gel, patches or pellets.

10 tests explainedAI-verified against cited sources. Awaiting expert reviewLast reviewed 2026-10-19

On testosterone therapy, a few tests come up again and again: testosterone itself, hematocrit and, for many men, PSA. When to draw depends on the type of testosterone you use, so the timing of the test matters as much as the number. Checks are closer together in the first year and spread out once things are steady.

The tests that matter most

Most important first. Each one links to its full page, where the note for this group sits near the top.

Hematocrit
Testosterone increases red blood cell mass, so hematocrit is a key safety test. The Endocrine Society suggests checking it before starting, at 3 to 6 months, then yearly. It treats a hematocrit above 54% as a reason for the clinician to review treatment, including checking for causes such as low oxygen levels or sleep apnea.
Sources: Endocrine Society (2018) and U.S. Food and Drug Administration (2025)
Men, 13+
37.5–51 %
Women, 13+
34–46.6 %
Testosterone, Total
Total testosterone shows where your dose lands. The Endocrine Society aims for the middle of the normal range. The right time to draw depends on the type of testosterone you use.
Source: Endocrine Society (2018)
Men, 20+
264–916 ng/dL
Men, 18–19
150–785 ng/dL
PSA, Total (Prostate-Specific Antigen)
For men 55 to 69, or 40 to 69 with a higher chance of prostate cancer (such as African American men, or men whose father, brother or son had it), the Endocrine Society suggests talking through PSA monitoring. For those who choose it, PSA is checked before starting and at 3 to 12 months, then on the usual screening schedule.
Source: Endocrine Society (2018)
Men
0–4 ng/mL
Men, 40–49
0–2.5 ng/mL
Hemoglobin
Hemoglobin rises along with hematocrit on testosterone. The FDA label lists both among the tests to check periodically, and notes that a higher red cell mass may raise the risk of blood clots.
Sources: U.S. Food and Drug Administration (2025) and Endocrine Society (2018)
Men, 16+
13–17.7 g/dL
Women, 16+
11.1–15.9 g/dL
Estradiol (E2)
Men need some estradiol too. The Endocrine Society notes it helps prevent gains in body fat and hot flashes. In the FDA label's studies of one testosterone gel, estradiol levels moved in step with testosterone.
Sources: Endocrine Society (2018) and U.S. Food and Drug Administration (2025)
Usual adult range
7.6–42.6 pg/mL
HDL Cholesterol
Testosterone therapy is linked to a small drop in HDL cholesterol, the Endocrine Society says. The FDA label suggests checking the lipid profile periodically, especially after starting.
Sources: Endocrine Society (2018) and U.S. Food and Drug Administration (2025)
Usual adult range
40 and above mg/dL
Sex Hormone-Binding Globulin (SHBG)
SHBG is a protein that binds testosterone in the blood. Obesity, diabetes, aging and HIV can shift it, and in those cases the Endocrine Society suggests measuring free testosterone too, since total testosterone alone can mislead.
Source: Endocrine Society (2018)
Men, 20–49
16.5–55.9 nmol/L
Men, 50+
19.3–76.4 nmol/L
Testosterone, Free
Free testosterone is the part not bound to proteins. The Endocrine Society prefers measuring it by equilibrium dialysis, or calculating it from total testosterone, SHBG and albumin with an accurate formula.
Source: Endocrine Society (2018)
Men, 18+
47–244 pg/mL
Women, 18–30
0.8–7.4 pg/mL
Luteinizing Hormone (LH)
LH is mostly measured before treatment, together with FSH, to help tell whether low testosterone comes from the testes or from the pituitary, the Endocrine Society says. It also notes that biotin supplements can throw off LH and FSH tests.
Source: Endocrine Society (2018)
Usual adult range
1.7–8.6 mIU/mL
Follicle-Stimulating Hormone (FSH)
Testosterone therapy is linked to lower sperm production, the Endocrine Society says. The FDA label for one testosterone gel notes that LH and FSH fell during treatment, and that large doses can lower sperm production by turning down FSH.
Sources: Endocrine Society (2018) and U.S. Food and Drug Administration (2025)
Usual adult range
1.5–12.4 mIU/mL

Ranges shown are the usual adult ranges labs print. The range on your own report is the one your result is judged against.

Getting results you can compare

When to draw depends on the type of testosterone. The Endocrine Society suggests midway between cypionate or enanthate injections, just before the next dose for undecanoate injections and pellets, 3 to 12 hours after putting on a patch, and 2 to 8 hours after applying a gel once you've used it for at least a week.
Source: Endocrine Society (2018)
The Endocrine Society suggests the first testosterone check 3 to 6 months after starting, and a hematocrit check at the same point.
Source: Endocrine Society (2018)
Biotin supplements can throw off LH and FSH tests, the Endocrine Society notes. Tell your clinician or lab if you take biotin.
Source: Endocrine Society (2018)

Good to know

Testosterone therapy is linked to lower sperm production and fertility. The Endocrine Society recommends against it for men planning to have children soon, so if children are a goal, it's worth raising early with your clinician.
Sources: Endocrine Society (2018) and U.S. Food and Drug Administration (2025)
The Endocrine Society looks at how PSA changes from your starting value. For men who choose PSA monitoring, it suggests a urology referral for a confirmed rise of more than 1.4 ng/mL in the first 12 months, or a confirmed PSA above 4 ng/mL at any time. A high result is repeated first to confirm it.
Source: Endocrine Society (2018)
A raised hematocrit is more common with injections than with gels, and in older men than younger men, the Endocrine Society says. It is linked to the dose and to testosterone levels in the blood.
Source: Endocrine Society (2018)

Questions you could ask

When should my blood be drawn relative to my dose?
How often should we recheck my hematocrit?
Which PSA schedule fits my age and family history?
If I'd like to have children in the future, how does that change my testing?
Is it worth checking estradiol along with my testosterone?

Sources

Testosterone Therapy in Men With Hypogonadism: An Endocrine Society Clinical Practice Guideline, Endocrine Society (2018)
AndroGel 1.62% (testosterone gel) prescribing information, U.S. Food and Drug Administration (2025)

AI-verified against cited sources. Awaiting expert review. Last reviewed 2026-10-19. How we build and check these pages.

Educational information, not medical advice. Blood Test Tracker doesn’t diagnose or treat, and it doesn’t replace your clinician. Talk with your clinician before changing medications, supplements or care.