TRT (Testosterone Replacement Therapy) Blood Test, from our experts to you.
Dr Sam Rodgers MBBS, MRCGPChief Medical Officer

When should I take a TRT blood test?
We recommend taking this test before starting TRT and six months after for monitoring purposes.
Why is PSA included?
Our test also includes testing your Prostate Specific Antigen (PSA) level. Whilst research indicates that it is unlikely that TRT increases the risk of prostate cancer, caution is advised - particularly if you already have prostate cancer. The PSA marker can help to detect prostate cancer earlier. However, it has several shortcomings when used as a screening test. Besides being increased by prostate cancer, urinary tract infection, recent ejaculation, and even some forms of exercise can also raise PSA.
Currently, the most reliable way of determining whether someone has a true positive or false positive is by performing a prostate biopsy. Because the PSA test has a high false positive rate, many of these prostate biopsies will have been unnecessary.
What could PSA results mean?
There is a risk of PSA being positive when no cancer is present (a false positive). If we take 100 men with a high PSA result, then approximately 75 of them will have a false positive result, and 25 will have a true positive (i.e. they will have prostate cancer). PSA tests can also cause false negative results. This means that the PSA is in the normal range, but the person has underlying prostate cancer. PSA levels can remain normal in the early stages of prostate cancer, providing false reassurance. If we test 100 men with prostate cancer, then approximately 15 would have a normal PSA result (a false negative). In some cases, prostate cancer grows very slowly, and it may never cause symptoms or shorten lifespan, so a significant proportion of the men who receive a true positive result may undergo surgery they did not need.
What's Included?
How to prepare for your test
Special Instructions
Prepare for your TRT (Testosterone Replacement Therapy) Blood Test by following these instructions. Please take your sample before 10am. Avoid heavy exercise for 48 hours beforehand. Please avoid ejaculating for 48 hours prior to this test. Hormonal contraception can affect this test, taking a break from this and using barrier contraception will give more accurate results. If you use hormone gels, pessaries, patches, or tablets, we strongly recommend selecting a venous sample to minimise contamination sometimes seen with finger-prick tests. Otherwise, administer any hormone supplements using gloves, and make sure your fingers have not been in contact with hormone supplements for at least four weeks before taking the test. Hormones can be absorbed deep within the skin even after minimal contact and remain there for weeks despite vigorous handwashing. Do not take biotin supplements for two days before this test, discuss this with your doctor if it is prescribed. If you are a woman take this test two to five days after the start of your period, ideally on day three. It can be taken any time if you do not have periods.