Short answer: There is no single number. The Endocrine Society guideline suggests aiming for the mid-normal range on treatment, and the American Urological Association guideline puts that at 450 to 600 ng/dL total testosterone. The FDA labels judge products against a normal range of about 300 to 1,000 or 1,100 ng/dL. What your result means also depends on when it was drawn relative to your last injection, and on your lab's own range.
Endocrine Society (2018): the guideline suggests that clinicians "aim at achieving T concentrations in the mid-normal range during treatment with any of the approved formulations", while weighing patient preference, how the product behaves in the body, side effects, treatment burden and cost. It does not set one number for every lab and product.
American Urological Association (2018): the AUA guideline says to adjust the dose to reach a total testosterone level in the middle third of the normal reference range, and gives that as 450 to 600 ng/dL. It says to use the minimal dosing needed to get there. It uses 300 ng/dL as a reasonable cut-off below which testosterone is low when making the diagnosis.
The AUA guideline also says the goal is normal levels together with better symptoms. If symptoms do not improve after levels reach the target, it says clinicians should question whether low testosterone was the cause, and discuss stopping treatment after 3 to 6 months.
Normal ranges depend on the lab and the test method. To make results comparable, a 2017 study cross-calibrated four large studies of men in the US and Europe against a CDC reference method. In healthy, non-obese men aged 19 to 39, it put the normal range at 264 to 916 ng/dL, with a middle value of 531 ng/dL.
The FDA labels for injected products use their own normal range to judge whether a product worked:
| Label | Normal range used | Dose-adjustment target |
|---|---|---|
| Xyosted (weekly enanthate under the skin) | 300 to 1,100 ng/dL, average over the week | Trough 350 to 650 ng/dL, measured 7 days after a dose |
| Aveed (undecanoate every 10 weeks) | 300 to 1,000 ng/dL, average over the interval | None given |
| Depo-Testosterone (cypionate) | Not given | None given; dose adjusted by response and side effects |
In the Xyosted trial, 90% of men had a weekly average within 300 to 1,100 ng/dL at week 12. In the Aveed trial, 94% had an average within 300 to 1,000 ng/dL after the third injection.
Injected testosterone rises after each shot and falls before the next, so one person on a steady dose can get very different results on different days. A trough level, taken right before the next shot, is the low point; a level a day or two after the shot is near the high point. In the Xyosted label study the average peak was 790 ng/dL and the average low was 436 ng/dL across the same week.
The labels and guidelines pick their own timing. The Xyosted label measures the trough, 7 days after a dose, after 6 weeks of dosing and 6 weeks after any dose change. The AUA guideline says men on cypionate or enanthate injections should be tested no earlier than three to four dosing cycles in, Aveed users halfway between the first two 10-week injections, and everyone every 6 to 12 months after that.
Because of this, the same number can mean different things. A 450 ng/dL trough and a 450 ng/dL reading two days after a shot do not describe the same dose. Which timing your prescriber wants, and what range they are aiming for, is worth asking before the draw.
Write down the date and time of the last injection with every lab result, and keep using the same lab if you can, since ranges and methods differ. Total testosterone is only part of the panel: the Endocrine Society says men on treatment should be monitored on a set plan that includes symptoms, side effects, testosterone and hematocrit, and prostate cancer risk in the first year. Dose Track logs each dose with its time, and lab results next to them, so every reading carries its place in the injection cycle.
Read more on Dose Track: Total vs free testosterone and SHBG · TRT steady state explained · Weekly vs twice-weekly TRT injections · Low testosterone · Trough level (glossary) · Free testosterone (glossary)