The PSA test is a blood test used primarily to screen for prostate cancer.
PSA is mostly found in semen, which also is produced in the prostate. Small amounts of PSA ordinarily circulate in the blood.
The PSA test can detect high levels of PSA that may indicate the presence of prostate cancer.
However, many other conditions, such as an enlarged or inflamed prostate, can also increase PSA levels. Having sex a lot can also raise the PSA levels.
- PSA-raising factors. Besides cancer, other conditions that can raise PSA levels include an enlarged prostate (benign prostatic hyperplasia, or BPH) and an inflamed or infected prostate (prostatitis). Also, PSA levels normally increase with age.
- PSA-lowering factors. Certain drugs used to treat BPH or urinary conditions, and large doses of certain chemotherapy medications, may lower PSA levels. Obesity can also lower PSA levels.