context: Prostate ultrasound and biopsy are tests that check the abnormal results of a digital rectal exam or an elevated prostate-specific antigen ( PSA) blood test. Prostate ultrasound uses a probe about the size of a finger that's inserted a short distance into your rectum. This probe creates harmless sound waves. You can't hear them, but they bounce off the surface of your prostate. A machine records the sound waves and turns them into videos or photos of your prostate gland. The probe can provide images at different angles to help your doctor estimate the size of your prostate and spot abnormal growths. A prostate biopsy uses transrectal ultrasound imaging (meaning it goes through the lining of your rectum) to guide several small needles through the rectum wall into areas of the prostate where the doctor sees something unusual. The needles remove a tiny amount of tissue. This is called a biopsy. Most doctors take six or more biopsies to test various areas of the prostate. The tissue samples are checked in a lab to see if they're cancerous. The results will help your doctor diagnose disorders and diseases in your prostate. If the doctor finds cancer, they'll be able to grade it and figure out how aggressive, or likely to spread, it is. This helps them decide how to treat the cancer. Some doctors do the biopsy through the perineum, the small area of skin between your scrotum and rectum. Researchers are looking into new biopsy procedures to get more accurate results. Here's how to get ready for the ultrasound and biopsy. Special conditions. Tell your doctor if you have a lung or heart condition or any other diseases, or if you're allergic to any medicines. Also let them know if you have an artificial heart valve or if you've ever been told you need to take antibiotics before a dental or surgical procedure. If you have any of these conditions, you'll get antibiotics to take before the biopsy. Medications. Tell your doctor if you're taking clopidogrel ( Plavix), rivaroxaban ( Xarelto), warfarin ( Coumadin), or other blood thinners. You may need to stop taking them a week before the procedure. The doctor might prescribe another method to thin your blood. The week before, don't take aspirin, products with aspirin, anti-inflammatory drugs such as Advil, Motrin, or Naprosyn, or indomethacin ( Indocin). You'll get antibiotics to take the night before or morning of the test to prevent infection. Don't stop taking any medication without talking to your doctor first. Eating and drinking. Eat a light breakfast or lunch before the procedure. Drink only clear liquids (which include juices, broths, and gelatin) the morning of the test. Enemas: You'll get one enema before the procedure to empty your colon and minimize the risk of infection. The doctor may have you take the enema at home. Try to hold the enema solution for at least 5 minutes before you release it. A doctor or nurse will explain the test in detail, including possible complications and side effects. You'll be able to ask questions. A doctor experienced in prostate ultrasound and biopsy does the procedure. It should only last 10 to 20 minutes. You'll lie on your left side with your knees drawn up. The doctor inserts the ultrasound probe into your rectum and takes the biopsy samples. They'll use a medication to numb the area, but it may hurt a little or feel uncomfortable. The doctor will send the biopsy to a lab for analysis. They'll discuss the results with you when they're ready, which is usually within a week. Meanwhile: You can go back to your normal meals and activities. Do NOT take aspirin, products with aspirin, anti-inflammatory drugs such as Advil, Motrin, or Naprosyn, or indomethacin ( Indocin) for at least 3 days after the procedure. Drink six to eight glasses of water every day for 3 days after the test to help flush your urinary system. You may notice a small amount of blood in your urine, semen, or stool up to 7 days afterward. This is normal. If your rear end is sore, soak in a warm bath for 20 minutes. Take your antibiotics until all the pills are gone. If you miss a dose, take it when you remember and then go back to your regular schedule. Call the nearest emergency department if: You have a fever above 100.4 degrees F (38 C). You have trouble peeing. Your urine is bloody and doesn't clear after you drink extra fluids. You see a blood clot in your urine.