Prostate Specific Antigen

Prostate specific antigen, or PSA, is a protein naturally produced by your prostate gland. This blood test measures the amount of PSA circulating in your bloodstream and is one of the most widely used markers for keeping an eye on prostate health. Understanding your PSA level matters because the prostate is a small but important gland that sits just below the bladder, and changes in how it functions can have a real impact on your day-to-day quality of life. Keeping tabs on your PSA over time gives you and your healthcare team a useful baseline, making it easier to spot any meaningful shifts early on. Think of PSA a bit like a smoke detector for your prostate.

The gland produces this protein as part of its normal job, but when the prostate is under stress, whether from inflammation, enlargement, or other changes, it can release more PSA into the blood. A single reading on its own does not tell the whole story; what matters most is the trend over time and how your result sits within the expected range for your age. Several perfectly ordinary things can temporarily nudge your PSA level upwards. Vigorous cycling, recent ejaculation, a urinary tract infection, or even a digital rectal examination shortly before the blood draw can all cause a short-lived rise. Age is another important factor: PSA levels tend to creep up naturally as you get older, which is why age-adjusted reference ranges exist.

Certain medications and supplements may also influence your reading. If your result falls outside the expected range, or if you notice a change from previous tests, it is well worth having a conversation with your GP. They can look at your result in the context of your age, symptoms, and medical history, and advise on whether any further investigation would be helpful.

PSA is an important clinical marker for prostate cancer, the commonest form of cancer in men. However, the PSA test in isolation has high sensitivity but low specificity for cancer, so abnormal results must always be discussed with your doctor.