The prostate-specific antigen (PSA) test is one step in diagnosing cancer, but it's far from foolproof. Only one in four men with moderately high PSA levels has prostate cancer, and some men with prostate cancer test normally. "I like to think of PSA as 'Please Stay Alert,'" says Ash Tewari, M.D., director of the LeFrak Center for Robotic Surgery at Weill Cornell Medical Center. Help your doctor make the most of your results by speaking up if any of these potentially PSA-altering conditions apply to you.
You take medication containing finasteride
Propecia, the hair-loss drug, and Proscar, a drug used to treat prostate enlargement, can lower your PSA by half, Dr. Tewari says. Finasteride inhibits an enzyme that helps hormones act on your prostate, and without that enzyme, your prostate won't make as much PSA, whether you have cancer or not.
Some common medications can lower your PSA if you've been taking them for 5 years or longer. A recent study in the Journal of Clinical Oncology found that men who took aspirin or ibuprofen, statins, or thiazide diuretics (blood pressure meds) had PSA levels 6 percent, 13 percent, and 26 percent lower, respectively, than men who didn't pop these pills.
One recent study in the journal Prostate showed that when men with high PSA readings took supplements containing curcumin and soy isoflavones, their levels dropped 45 percent. It's not clear whether some supplements alter just your PSA or your actual cancer risk. Make sure your doctor knows about any supplements you take, just in case.
You had a colonoscopy
"Any manipulation in that area can affect PSA," Dr. Tewari says. The journal International Urology and Nephrology reported that nearly half of men had elevated PSA levels 24 hours after a colonoscopy; some had elevated levels a month later. For this reason, ask your doctor to test your PSA before a colonoscopy or digital rectal exam.
Let your doctor know if you've experienced trauma in the area, if you have to pee more often, or if you experience a burning sensation when you pee. Those could be signs of benign prostatic hyperplasia (a noncancerous enlargement) or prostatitis (an inflammation or infection of the prostate). Both can raise your PSA.