Doctors, sports officials, and employers may request these tests.
For example, a doctor may ask for a urine screen to determine if a person is taking a prescribed opioid medication in a way other than the doctor intended.
A member of an emergency services team may request a urine drug screen if they suspect that a person is behaving strangely or dangerously due to the influence of drugs.
Drug and alcohol rehabilitation programs may request urine drug screens at initial assessments and follow-up appointments.
Learn more about the treatments for addiction here.
Many sporting officials require urine tests to check whether athletes have used performance-enhancing drugs, such as anabolic steroids.
The World Anti-Doping Agency regulates the use of performance-enhancing substances in many global sports events. Making sure that all athletes are performing without these drugs
Some employers request that new staff members take urine drug tests. Or, staff may have to do this on a regular basis.
This is more common in workplaces that require high levels of safety. For example, United States
Laws about employee drug testing differ geographically. A person should check with local authorities.
A urine drug screen can detect
Urine screens can also detect nicotine and cotinine, which the body produces when it breaks down nicotine.
Though a urine test can indicate the presence of alcohol, if a health or legal authority suspects that a person has been drinking in excess, they are more likely to request a breath or blood test.
Learn more about other types of substance tests here.
A doctor or trained technician usually performs a urine drug screening.
There are several types of these tests. An immunoassay (IA) test is
However, IA tests can give
Another type can confirm the results of an IA test. This is called gas chromatography-mass spectrometry (GC-MS). A GC-MS test is
Usually, people only request GC-MS tests as follow-ups because they are more expensive, and the results take longer.
Generic IA tests can show cocaine, amphetamines, opioids, cannabinoids, and PCP. A doctor may require a more specialized IA test to check for synthetic and semisynthetic opioids, such as methadone.
It is important to note that consuming certain legal substances
To minimize the risk of false positives, urine drug screens have cut-off levels. This means that a result is only positive when the test detects an amount of a drug that is above a certain level. Cut-offs also reduce the likelihood of testing positive due to only passive exposure to a drug. Secondhand smoke is one example of passive exposure.
Also, both IA and GC-MS tests can produce false-negative results. These fail to indicate recent drug use. A false-negative result can occur when urine is very diluted, for example.
Many factors can affect when a test can detect a certain drug. Some factors include:
- the person’s body mass
- their hydration levels
- the acidity of their urine
- how long ago the drug use occurred
Overall, the more frequently and heavily drug use occurs, the longer the drug will be detectable.
Below, for example, we show how long urine tests can detect cannabis.
Other typical drug detection ranges include:
The test requires little preparation. Usually, a person just has to urinate into a plastic container and return the urine sample to the technician or doctor.
They then measure the temperature of the urine sample to make sure it is suitable for testing. They seal the sample in a plastic bag. If a person cannot return their sample to a medical professional within 1 hour, they should seal it in a plastic bag and store it in a refrigerator.
A technician may accompany the person to make sure that they are giving the sample correctly. The technician should explain the reason for this supervision.
It is important to note that certain medicines and supplements can cause false-positive results.
A person should tell the test provider if they are taking any:
- prescription medications
- over-the-counter medicines
- herbal remedies
Urine drug screen results usually come back within a few days or on the same day.
If a result is positive, a person may need to take a second test for confirmation. This may be a GC-MS test, which gives more accurate results.
The person who carried out the test or a medical review officer will explain the results.
A urine drug screen can quickly, effectively detect some illegal and prescription drugs. Doctors, sports officials, and employers may request this type of test for various reasons.
The screening can detect a range of substances, including cannabis, nicotine, barbiturates, and opioids such as heroin and methadone. Some remain traceable in the body longer than others.
If an initial result is positive, a person may need to take a second, more accurate test.