Drug Testing


What is drug testing?

Drug testing is a way to evaluate the type and possibly the amount of legal or illegal drugs taken by a person.

Test Details

How is a drug test performed?

Drug testing can be performed from small samples taken of your blood, hair, saliva, breath, or most commonly, your urine. For a urine sample, you will be asked to urinate into a clean container provided to you. In some instances, you may need to provide your urine sample in the presence of a nurse or technician to make sure that the sample did indeed come from you. For a blood sample, a small amount of blood is taken from a vein in your arm or hand and is then sent to the laboratory for analysis. For a hair sample, some hair from your head is sent to the laboratory for analysis.

How should I prepare for a drug test?

No special preparations are necessary. Drug testing is often performed as an emergency test, can be a scheduled test, or be conducted on a random basis, or (for example, to meet ongoing employment requirements). Depending on the circumstances of the testing, you may be asked to identify medications or supplements that you are taking.

Are drug testing home kits available?

Yes. There are kits that can test urine samples in the privacy of your own home. Some kits may use breath, saliva, or hair instead. The accuracy of some of these products is variable. They generally are less sensitive than the formal tests done in a laboratory. This means that a home test could be negative, but a laboratory test could be positive.

Results and Follow-Up

How accurate are these tests?

Drug testing is extremely accurate and reliable when all aspects of the testing process are done properly.

What is the purpose for this test?

This test is commonly used to check for illegal drug use by employees (before an offer of employment is made and randomly at any time after hire). A drug test can also be used to evaluate possible accidental or intentional overdose or poisonings, to monitor compliance with a drug rehabilitation program, and to determine the presence or absence of drugs for medical and or legal purposes. Some tests are only approved for use in certain situations.

If the test is used as a drug screen, many habit-forming prescription drugs can be detected as well as illegal drugs and alcohol. Some of the most commonly tested for chemicals include:

Additional Details

Do insurance companies cover drug testing?

Generally yes, as long as the testing is part of some larger medical treatment plan such as addiction treatment, pain management, or acute hospital care. When conducted or required by your employer, there should be no cost to you.

Last reviewed by a Cleveland Clinic medical professional on 07/24/2019.


  • American Society of Addiction Medicine. Drug Testing: A White Paper of the American Society of Addiction Medicine (ASAM). (http://www.asam.org/docs/default-source/publicy-policy-statements/drug-testing-a-white-paper-by-asam.pdf?sfvrsn=0) Accessed 7/19/2019.
  • National Institute on Drug Abuse. Commonly Abused Drugs Charts. (https://www.drugabuse.gov/drugs-abuse/commonly-abused-drugs-charts#mdma) Accessed 7/19/2019.
  • Palac SM. Chapter 212. Seizures. In: McKean SC, Ross JJ, Dressler DD, Brotman DJ, Ginsberg JS. eds. Principles and Practice of Hospital Medicine. New York, NY: McGraw-Hill; 2012. Accessed 7/19/2019.
  • Center for Substance Abuse Treatment. Substance Abuse: Clinical Issues in Intensive Outpatient Treatment. Rockville (MD): Substance Abuse and Mental Health Services Administration (US); 2006. (Treatment Improvement Protocol (TIP) Series, No. 47.) Appendix B. Urine Collection and Testing Procedures and Alternative Methods for Monitoring Drug Use. Available from: nlm.nih.gov. (http://www.ncbi.nlm.nih.gov/books/NBK64092/) Accessed 7/19/2019.

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