Prostate specific antigen (PSA) is produced by healthy cells in the prostate, so it’s normal to have a small amount of PSA in your blood. The amount rises as you get older and your prostate gets bigger. Prostate problems, such as an enlarged prostate or prostatitis, can cause your PSA level to rise – but lots of other things can affect your PSA level too.
A urine infection – You may have a test for a urine infection as this can raise your PSA level. If you have an infection, you’ll be given treatment for this. You’ll need to wait until the infection has gone – around six weeks – before you have a PSA test.
Vigorous exercise – You might be asked not to do any vigorous exercise, especially cycling, in the 48 hours before a PSA test.
Ejaculation – You may be asked to avoid any sexual activity that leads to ejaculation in the 48 hours before a PSA test.
Anal sex and prostate stimulation – Receiving anal sex might raise your PSA level for a while. Having your prostate stimulated during sex might also raise your PSA level. It might be worth avoiding this for a week before a PSA test.
Digital rectal examination (DRE) – Having a DRE just before a PSA test might raise your PSA level a small amount. Your doctor might avoid testing your PSA for a week if you’ve just had a DRE.
Prostate biopsy – If you’ve had a prostate biopsy in the six weeks before a PSA test, this could raise your PSA level.
Medicines – Let your GP or practice nurse know if you’re taking any prescription or over-the-counter medicines, as some can affect men's PSA levels. For example, 5-alpha-reductase inhibitors such as finasteride (Proscar®) or dutasteride (Avodart®), which can be used to treat an enlarged prostate, can reduce your PSA level and give a false test result.