Drug Screening

A toxicology drug screening test examines blood or urine for the presence of drugs. Drug screening may test for a specific drug or for up to 30 different drugs, depending on the individual case. Screening is often done on a urine sample instead of blood, because urine tests are usually easier to do than blood tests and a wider number of drugs can be detected in the urine. Also, a drug may be detectable for a longer period of time in urine than in blood.

A toxicology screen can be done to test for drug use in the workplace, especially for people in positions that involve public safety (such as bus drivers). A drug screen may also be a normal part of the application procedure for some jobs. This may be done on either a blood or urine sample.

On the day of the test, you should be prepared to list the medications (prescription and nonprescription), herbal supplements, vitamins, and other substances you are taking, because they may interfere with the testing. You will need to sign a consent form that says you understand the risks of the test and agree to have it done. As you read the consent form, ask your doctor any questions you may have about the test and discuss any concerns you may have about your need for the test, the risks of the test, and how it will be done.

If you are having a blood test, you may feel nothing at all from the needle puncture, or you may feel a brief sting or pinch as the needle goes through the skin. Some people feel a stinging pain while the needle is in the vein. However, many people do not feel any pain (or have only minor discomfort) once the needle is positioned in the vein. There is very little risk of complications from having your blood drawn from a vein. You may develop a small bruise at the puncture site. You can reduce the risk of bruising by keeping pressure on the site for several minutes after the needle is withdrawn.

Collecting a urine sample normally does not cause any discomfort. A trained person of the same sex may need to witness the urine collection. This may make you feel uncomfortable. There are no risks associated with collecting a urine sample.