Prostate-Specific Antigen (PSA) is a protein produced primarily by the cells of the prostate gland. A blood test measuring its level is a common tool used in prostate health screening. While an elevated PSA level can sometimes indicate prostate cancer, it is not a specific marker for malignancy and can be raised by numerous non-cancerous factors. The primary goal of preparing for a PSA test is to eliminate these temporary influences, which can artificially inflate the reading. By taking steps to normalize your PSA level before the blood draw, you help your physician avoid unnecessary follow-up procedures that might be triggered by a misleadingly high score.
Understanding Temporary PSA Elevation
PSA levels fluctuate because the protein can leak into the bloodstream when the gland is irritated, compressed, or inflamed. One of the most common causes of temporary elevation is inflammation or infection of the prostate, such as prostatitis, or a urinary tract infection (UTI). The body’s immune response causes swelling that compromises the glandular structure, allowing more PSA to escape into the circulation. A physician will typically recommend delaying the test until the infection has cleared, which may require a wait of four to six weeks.
The size of the prostate gland itself also plays a role in the baseline PSA level. A non-cancerous enlargement known as Benign Prostatic Hyperplasia (BPH) causes a chronic, sustained increase. As the prostate grows larger with age, it produces more PSA simply because there are more cells present. More immediate spikes in PSA often follow direct physical trauma or manipulation of the prostate tissue, such as a cystoscopy, catheterization, or a vigorous Digital Rectal Exam (DRE).
Essential Physical and Activity Restrictions Before the Test
To obtain an accurate reading, the most immediate and controllable action is the avoidance of activities that cause muscular contraction or physical pressure on the prostate gland. Ejaculation, whether through sexual intercourse or masturbation, causes muscular contractions within the prostate that can forcefully push a significant amount of PSA into the bloodstream. Experts widely recommend abstaining from any activity leading to ejaculation for a minimum of 48 hours before the blood test to prevent this temporary elevation.
Intense physical activity, particularly those that involve direct pressure on the perineum, can similarly disrupt the prostate and increase PSA release. Cycling is the most cited activity to avoid, as the bicycle seat transmits pressure directly to the prostate area. It is generally advised to skip vigorous exercise, including long-distance running, spin classes, or cycling, for at least 48 hours prior to the test. Studies have shown that cycling can cause a statistically significant increase in PSA levels, making this precaution particularly important for older patients.
Any medical procedure that physically disturbs the prostate requires a much longer waiting period. A prostate biopsy causes substantial tissue trauma and inflammation, requiring a wait of approximately four to six weeks before a PSA test. Similarly, a Digital Rectal Exam (DRE) can cause a small, transient increase in PSA. It is best practice to have the blood drawn before the DRE if both are scheduled for the same appointment.
Reviewing Medication and Supplement Interference
Certain medications can significantly interfere with PSA results, requiring a discussion with your physician before the test. The most notable are 5-alpha reductase inhibitors (5-ARIs), such as Finasteride (Proscar) and Dutasteride (Avodart), commonly prescribed for an enlarged prostate or hair loss. These drugs work by shrinking the prostate and can reduce a man’s PSA level by up to 50% after six to twelve months of use.
Because 5-ARIs artificially suppress the PSA reading, a physician must be informed of their use to properly interpret the test result, often by doubling the measured PSA value. Other commonly used medications can also influence PSA levels, though to a lesser degree. Statins, used to lower cholesterol, nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen, and thiazide diuretics have been shown to be inversely associated with PSA levels, meaning they can cause a slight reduction over time.
On the other hand, certain hormonal supplements or high doses of testosterone may cause PSA levels to rise. It is prudent to provide your ordering physician with a complete list of all prescription drugs, over-the-counter medications, and supplements you are taking. This comprehensive review ensures that any necessary adjustments to the test result can be made, preventing either a false-low or a false-high reading.