How to Prepare for a Testosterone Blood Test and Get a Clear Result

A testosterone result can steer big decisions, so it is worth getting a reading you can trust. A draw at the wrong time of day, after a short night or while you are fighting off a cold can make your level look lower than it usually is. A little planning makes your results much easier to read.

Why Morning Timing Matters

Testosterone rises and falls over the day. The Endocrine Society guideline notes that levels peak in the morning. MedlinePlus says the blood sample is usually taken between 7 and 10 a.m., when levels are typically highest.

An afternoon result may come back lower simply because of the clock. That is why the American Urological Association (AUA) guideline calls for testing in the early morning.

If you work nights or rotating shifts, "morning" can be hard to pin down. Tell your clinician your schedule before you book, and ask how to time your draw.

Why You Need Two Tests

The AUA guideline says low testosterone should be diagnosed only after two total testosterone tests taken on separate occasions, both in the early morning. A diagnosis also needs symptoms or signs, not just a number.

One test is not enough because levels vary from day to day. The Endocrine Society guideline reports that 30% of men with an initial result in the low range have a normal level when the test is repeated. A second test helps sort out a pattern from a one-off dip.

How to Prepare, Step by Step

1. Get your lab orderAlternative Health Grand Forks can give you a lab order by phone. Call (218) 274-4500 and Will can help. The lab bills for the tests separately.
2. Book an early drawChoose the earliest slot you can, ideally between 7 and 10 a.m. If you work nights, ask your clinician how to time it first.
3. Sleep as normally as you canAim for a regular night of sleep before the test. Avoid booking the morning after a night shift or a very short night.
4. Fast if the lab asksThe Endocrine Society guideline describes testing while fasting, because food and sugar can lower testosterone. Follow the fasting instructions from your clinician or the lab, and ask whether water is fine.
5. Take your usual medicinesMedlinePlus advises telling your provider about everything you take and not stopping any medicine unless your provider tells you to.
6. Reschedule if you are sickIf you have a fever, the flu or another acute illness, call and move the test. Rescheduling is free.
7. Repeat on another dayBook the second test on a different morning, with the same preparation, so the two results can be compared fairly.

What Can Throw off a Result

Some things lower a reading for a while without meaning your usual level is low. The Endocrine Society guideline says men should not be tested while they have or are recovering from an acute illness, or while taking short-term medicines that suppress testosterone, such as opioid pain medicines.

• Illness. A recent infection, surgery or hospital stay can lower testosterone for a while.
• Short sleep. In a small study of 10 healthy young men, one week of sleeping about 5 hours a night lowered daytime testosterone. The authors called for more research, but it is one more reason to test after normal sleep.
• Food. Eating or drinking sugar before the draw may lower the result, which is why fasting is often requested.
• Some medicines. The Endocrine Society lists opioids and glucocorticoids (steroid medicines) among causes of low testosterone. Testosterone products, anabolic steroids and some supplements can also change results.
• Health conditions. Obesity, diabetes and sleep disorders such as sleep apnea affect testosterone levels too. These are not errors; they are part of the picture your clinician will look at.

Other Labs Often Ordered with It

Your clinician may order other tests on the same draw or after the first results. The AUA guideline describes several:

• Luteinizing hormone (LH) for men with low testosterone, to help find where the problem starts. The Endocrine Society also recommends follicle-stimulating hormone (FSH).
• Prolactin when testosterone is low and LH is low or normal.
• Hemoglobin and hematocrit, part of a blood count, before any testosterone treatment.
• PSA (prostate-specific antigen) for men over 40 before treatment.
• Estradiol if you have breast tenderness or swelling.

The Endocrine Society guideline also describes measuring free testosterone in some men, such as those with obesity or diabetes, whose binding proteins may be affected.

What to Bring to Your Consultation

• Copies of any past testosterone results, with the date and time of day each was drawn
• A list of all your medicines and supplements, with doses
• Any testosterone, anabolic steroid or hormone products you use now or have used
• Your work and sleep schedule, especially if you work nights or rotating shifts
• Notes on your symptoms and when they started
• Any recent illness, surgery or hospital stay
• Whether you might want children in the future

If your past results are with another clinic, the office can explain how to have them sent. Records can be faxed to (701) 757-0974, or downloaded from your patient portal and emailed to info@alternativehealthgf.com.

Next Steps

To get a lab order or book a visit, see our testosterone consultation page or contact the office. If you may want children, read testosterone therapy and fertility first, and for the bigger picture, see what a low testosterone evaluation can and cannot tell you.