What should you know about a urinalysis drug test?

A urinalysis drug test checks a urine sample for selected drugs or their breakdown products, but an initial result needs clinical interpretation and may require confirmation. It is different from a routine urine test, which may look for signs of infection, blood, protein, glucose, or kidney problems. The substances included depend on the test ordered and the laboratory method used.

A positive screening result means that the test detected a substance or a related chemical signal above the laboratory's reporting threshold. It does not by itself establish when a substance was taken, how much was used, or whether someone was impaired. Cross-reactions and prescribed medicines can affect some screening tests, so a clinician may request a more specific confirmatory test. A negative result means the tested substance was not detected under that test's conditions; it does not rule out every drug or every past exposure.

Tell the testing professional about prescribed medicines, pharmacy medicines, supplements, and relevant medical treatment before the sample is assessed. Do not stop a prescribed medicine to alter a result. A urine sample may also be checked for identification and sample validity according to the setting's procedures.

Bring an accurate list of medicines and supplements, including the dose and when you last took each one. Follow the collection instructions: wash your hands, use the provided container, avoid touching its inside, and return the sample as directed. Do not add water or another substance to the container. Ask how and when results will be shared, who can access them, and whether an unexpected screen will be confirmed before any decision is made.

If the test was ordered because of urinary symptoms, a separate urine test may be needed to investigate conditions such as a urinary tract infection or kidney infection. Testing for drugs does not diagnose those conditions.

Contact a clinician promptly if you have confusion, extreme sleepiness, trouble breathing, a seizure, or you cannot stay awake after taking a medicine or substance; call emergency services for severe or rapidly worsening symptoms. Seek medical assessment for fever with pain in the side or back, vomiting, or feeling very unwell, because these symptoms can occur with a kidney infection. Burning urination, urgency, or pelvic discomfort also deserves assessment, especially if symptoms persist or worsen.

Ask which substances the test includes, whether it is a screening or confirmatory test, and how prescribed medicines may be interpreted. You can also ask what an unexpected result means in your care setting, whether another sample or test is appropriate, and when you should expect an explanation of the findings.