Prior to the urine test, a physician will ask questions about the medical history to determine if the patient is taking any medications or vitamins that will interfere with the test’s results.

Most urine tests require little or no preparation. The physician may instruct the patient to restrict exercise and to reduce or stop taking certain medications or vitamins at some point prior to the test.

Many urine tests involve only a spot (single) sample. Patients will collect their urine sample in a physician’s office or clinic. Patients will receive a cup or other container that they will take into the bathroom. To capture a sample of urine, patients should try to obtain the specimen in midstream, a technique known as “clean-catch.” Preparation for this technique differs depending on the patient’s sex:

• Males. Wipe clean the head of the penis
• Females. Wash the area between the lips of the vagina with soapy water and rinse well.

Patients should not use the first sample upon awakening, but should instead wait to take a later sample. At least three hours should expire between the previous void and the episode used for obtaining the sample. As patients start to urinate, they should let a small amount of the initial urine fall into the toilet bowl. This will help clear the urethra (canal through which urine is discharged) of contaminants. Using a clean container, patients should capture between 1 and 2 ounces (30 to 60 milliliters) of urine before removing the container and finishing urinating into the toilet bowl.

After patients have cleansed, they should give the container and sample to a healthcare provider or assistant.

When obtaining a sample from an infant, an adult should prepare the child by washing the area around the urethral opening. Because infants cannot give voluntary samples, parents will have to rely on a urine collection bag to obtain the sample. This is a plastic bag with an adhesive paper on one end. For boys, the bag is placed over the penis and the adhesive is attached to the skin. For girls, the bag is placed over the labia. The child then wears a diaper over the bag.

The child’s caregiver will need to check frequently to see if the infant has urinated into the bag. Once the urine has been obtained, it is poured into a container and brought to a healthcare provider.

Some urine tests, such as those performed to measure levels of certain waste products (e.g., uric acid, bilirubin, creatinine) require a 24-hour sample rather than a spot sample. To collect a 24-hour urine sample the patient should:

• Get up in the morning of the first day of the test and empty the bladder. The urine should then be discarded in the toilet.
  
  
• Collect all subsequent urine in the provided container for the next 24 hours.
  
  
• Cap the container and keep it in a refrigerator or cool place during the collection period.
  
  
• Get up in the morning of the second day of the test and urinate into the container.
  
  
• Return the container to the physician’s office or a laboratory for analysis.

Afterward patients may resume exercise, medication and vitamin intake according to their physician’s instructions.

It typically takes two or three days for a laboratory to complete a urinalysis. A pathologist will use a microscope to examine the sample for signs of disease, such as bacteria, abnormal epithelial cells (which may indicate cancer), excessive numbers of red blood cells, white blood cells or other abnormal cells. In addition, physicians may order additional tests, such as blood tests, a biopsy, x-rays or an MRI, to verify a diagnosis. Treatment depends on the condition that is diagnosed.