undergraduate research drug test

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https://www.nist.gov/surf

Summer Undergraduate Research Fellowship (SURF)

2024 SURF Colloquium

August 13-15, 2024

Locations: NIST Gaithersburg, NIST Boulder, Center for Marine Debris Research in Waimanalo, HI, and Virtually on Zoom

• 2024 SURF Colloquium Schedule - includes Zoom links for virtual attendees
• 2024 SURF Abstract Book

You are invited to attend the Summer Undergraduate Research Fellowship (SURF) Colloquium scheduled August 13-15, 2024 at NIST Gaithersburg Bldg 101, NIST Boulder various buildings, and virtually on ZoomGov. The SURF program culminates in a three-day colloquium (August 13 - 15) where the undergraduates describe their research accomplishments in short oral presentations.  The SURF Colloquium begins with a plenary session on the morning of Tuesday, August 13, in Gaithersburg’s Green Auditorium, Boulder’s Bldg 81 Rm 1A116, and on ZoomGov. It continues that afternoon with parallel sessions. Additional parallel sessions will be held Wednesday, August 14, and Thursday, August 15. This summer's 152 undergraduates come from over 90 different schools and represent states and territories across the United States. 

NIST summer interns have improved MRI technology, studied medications, and more. Spend your summer with us for 11 weeks of hands-on lab experience with world-class mentors in one of NIST’s six labs or other offices. 

What You’ll Get  

In 2024, we expect to provide $7,810 for the 11-week summer stipend ($710 per week). If you’re participating in person, you’ll need to find your own housing. We will share a list of affordable housing options when you’re selected. Limited financial assistance for housing ($4,500) and travel (up to $500) is available for students who need to relocate for the summer. In-person local participants may receive support for commuting (varies) assistance.

Eligibility and Requirements

You must be a U.S. citizen or U.S. permanent resident able to provide proof on your application. You must be a full-time undergraduate student in an accredited two-year or four-year college in the U.S. First-year undergraduates and graduating seniors (seniors participating in the Winter or Spring Commencement) are eligible and encouraged to apply to the program.

Participants will work 40 hours per week (Monday through Friday during business hours). You must also: 

• Pass a background check 
• Provide proof of health insurance 
• Receive your payments by direct deposit 
• Be at least 18 years old 

How to Apply

Apply to the SURF program through USAJobs. All documents are required and must be submitted for consideration. Please submit your documents as PDF files if possible. Detailed instructions are available in the program  FAQs . 

surf [at] nist.gov (surf[at]nist[dot]gov)

Taking Measure Blog Posts from SURF Students

A Summer of Science: NIST Interns’ Stories of Their Time in the Lab

Clear as Glass: Studying Drug-Delivery Materials as a NIST SURF Student

Working to Improve Small-Scale MRIs: My Summer as a SURF Student at NIST

The NIST Summer Undergraduate Fellowship Program Goes Virtual

• International and Academic Affairs Office [email protected]

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The Undergraduate Student Internship Program provides domestic and international students with relevant research experience while they are pursuing an undergraduate degree. This year-round internship program is designed to complement your education with work experience related to your chosen field of study and offers opportunities in both technical and professional fields. This applies to entering first-year undergrads, current undergraduate students and post-bachelor’s interns. 

Current Opportunities

View all currently available undergraduate internships

Have a question for the Student Programs Office?

UH Drug Discovery Institute

UH-HEART Program

• Undergraduate Research Programs

Interested in a future in cardiovascular research?

Funded by the American Heart Association (AHA), the University of Houston’s – Houston Experience for Advancing Research and Training (UH-HEART) program provides transdisciplinary summer research experiences and translatable skills that prepare participants for future careers in cardiovascular-related research.

Up to five AHA research fellowships will be awarded to rising juniors, seniors, and recent graduates for a 10-week, full-time research experience. Participants will be engaged in a variety of cardiovascular research and enrichment activities under the guidance of a UH faculty sponsor.

All eligible students are invited to apply! Deadline to apply has been extended to Sunday, March 31. Please also consider applying to our new UH-CURE program .

Applications closed on Sunday, March 31, 2024. 

Thank you for applying to UH-HEART. Due to a large volume of applications, we are in the process of reviewing and will notify you as soon as possible.

Dr. Bradley McConnell 

Professor of Pharmacology Website

Nature of Work: A summer research experience in the McConnell laboratory would be working with a team of graduate students and postdoctoral fellow to either (1) characterize A-kinase Anchoring Proteins (AKAP) “signalosomes” in β-adrenergic receptor (βAR) mediated signaling, (2) define βAR-mediated “biased” signaling, or (3) investigate reprogrammed cardiac conducting cells for cardiac repair. By addressing clinically significant basic science questions, our overall objective in the McConnell Laboratory is to better understand cardiac signaling mechanisms and towards developing therapeutics for heart repair.

Dr. Renita Horton

Assistant Professor of Biomedical Engineering Website

Nature of Work: A summer research experience in the Cardiovascular Tissue Engineering Laboratory (CTEL) would focus on designing and building organs-on-chip microdevices and imaging engineered tissues for cardiovascular disease studies. Students will also gain exposure to 3D printing and cell culture techniques for tissue engineering applications.

Dr. Krishna Boini 

Assistant Professor of Pharmacology Website

Nature of Work: A summer research experience in the Boini laboratory would focus on studying obesity-induced Nlrp3 inflammasomes. Inflammasome activation is proposed as a key mechanism responsible for obesity-induced glomerular injury via its inflammatory and non-inflammatory actions. Thus, we will test whether obesity-induced Nlrp3 inflammasome activation contributes to glomerular injury. The findings from our studies will identify new mechanistic insights for targeting inflammasomes to develop novel therapeutic strategies for the treatment of End-Stage Renal Disease (ESRD) in obese patients.

Dr. Yang Zhang, 

Associate Professor of Pharmacology Website

Nature of Work: A summer research experience in the Zhang laboratory will study how an epigenetic enzyme that usually modifies the chromosomal DNA contributes to vascular cell dysfunction and thereby provokes vascular injury and artery hardening in the settings of obesity and diabetes. The molecular mechanisms will focus on the role of this enzyme in the regulation of lysosome function, autophagic flux, and exosomal signaling.

Dr. Preethi Gunaratne

Moores Professor of Biology and Biochemistry Website

Nature of Work: A summer research experience in the Gunaratne laboratory will have two areas of focus: (1) Precision Oncology Platforms focused on Remote Sensing Precancerous Lesion using Single Cell Sequencing and Discovering Actionable Fusions for developing mRNA Vaccines for Cancer Treatment and Prevention. (2) Discovering New Druggable Targets and Biomarkers for Remote Sensing Brain Changes from Opioid Addiction through the microRNA-Regulated Transcriptomic Changes from Drug Abuse. To achieve these goals, her lab has established a functional genomics platform that combines the latest Next-Generation Sequencing (NGS) and bioinformatics tools with high-throughput functional screens to identify critical drivers of biological networks during development and the perturbation of normal networks in complex diseases.

Dr. Yu Liu 

Associate Professor of Biochemistry Website

Nature of Work: A summer research experience in the Liu laboratory would focus on embryonic and adult stem cell theories and experimental practices. Currently, the Liu lab is using animal models to address how ectopic expression (transgenic) or deletion (knockout) of miR-322/503 affects normal heart function and the outcome of ischemic heart diseases.

Please note that individual research projects may vary from the descriptions due to availability or other factors.

• 3.0 GPA or higher. Extenuating circumstances will be considered
• Rising junior or senior in college, or immediate college graduate
• Be available for full-time participation in the 10-week program
• At the time of application, student must be a United States citizen, or a foreign national holding a student, exchange, or permanent resident visa, including an F-1, H1, H1B, J1, PR, TC or TN visa

A complete application includes:

• One-page Personal Statement on student’s interest in cardiovascular research, future career aspirations, and goals to accomplish in the program.
• Two Recommendation Letters submitted from the reference person through the online submission tab. Applicants must provide recommendation submission link to references. Please title document as “ [Applicant name] AHA 2024 ”
• Updated CV or Resume(PDF)
• Official Transcript(s)(PDF) preferred; unofficial transcripts (PDF) must contain proper identifying information, such as name, university, and semester.  
• All required fields completed

The online application form will open January 2024. Only completed applications, including reference letters, will be reviewed.

The application deadline is Sunday, March 31, 2024.

$6,000 stipend per participant for the ten-week program, with additional optional funding for travel to a national or international conference with a faculty mentor within six months of program completion.

Accepted fellows may elect to stay in  on-campus housing at any of the available facilities at an affordable rate. For additional help, please contact Dr. Tho Tran .

• Full-time participation in research and enrichment activities
• One-page narrative at the end of the program to be submitted to the AHA
• Completion of progression surveys throughout the program and beyond
• Annual update on academic and career activities
• Applications Open: January 2024
• Deadline for Applications and Letters of Recommendation: Sunday, March 31, 2024
• Applicants Notified: Friday, April 12, 2024
• Applicant Reply Deadline: Sunday, April 21, 2024
• Virtual Orientation Week of May 20, 2024
• Program Start: Tuesday, May 28, 2024
• AHA Basic Cardiovascular Sciences Conference: July 22-25, 2024
• Program End: Friday, August 2, 2023  

"From all the protocols, experiments, and facts I learned, what I appreciate the most about this program is the people I met on this journey."

— Robert Flores, University of St. Thomas, 2021 UH-HEART Fellow

About the Program

Established in 2021, the UH-HEART program is dedicated to shaping the upcoming generation of diverse cardiovascular researchers. The program's goals are to offer transdisciplinary research exposure and a toolkit of adaptable skills, preparing students for future careers in cardiovascular-related research. The progress of scientific innovation in cardiovascular research relies on the current training of a diverse community of aspiring scientists, both scientifically and demographically. To inspire promising undergraduates to explore cardiovascular research careers, it is crucial to provide them with robust research experiences that aid in discovering their passions. As societal health challenges become more intricate, instilling a transdisciplinary and collaborative mindset in students is equally important for unlocking innovative solutions.

Notable highlights of the program include a 10-week intensive, hands-on research experience under the guidance of excellent mentors, dedicated professional development training, and a cohort group travel to one of the largest cardiovascular research conferences globally.

BCVS Conference

This summer, the 2024 UH-HEART cohort is set to attend the American Heart Association (AHA) Basic Cardiovascular Scientific (BCVS) Sessions, a premier global conference for cutting-edge cardiovascular research. At this significant event, UH-HEART fellows will engage with other passionate scientists, delving into discussions and presentations on the latest therapeutics for cardiovascular diseases. They will connect with leading researchers in microRNAs, cardiac gene therapy, tissue engineering, and more. Crucially, fellows will forge valuable connections with like-minded colleagues keen on a research career. 

The BCVS is happening in Chicago, Illinois, from July 22 to July 25, and all fellows will have their lodging, travel, and registration expenses covered through their research stipend!

UH-HEART News

AHA Revives UH-HEART Program

Two Biology Students Complete UH-HEART Summer Program

Students Pumped Up for UH-HEART

"Throughout the program, I have had exposure to people with different degrees and paths, and it has been inspiring to hear from them. I have been able to really understand the experience of graduate students as I work alongside them every day in the lab." 

— Asha Ayyar, University of Texas at Austin, 2022

American Heart Association

The American Heart Association is a relentless force for a world of longer, healthier lives. As the nation’s oldest and largest voluntary health organization, the AHA advances groundbreaking research, provides lifesaving resources, and promotes healthier lifestyles.

AHA Summer Research Programs

Cardio SuRPH (Summer Undergraduate Research in Cardiovascular Physiology) Loyola University Chicago Stritch School of Medicine

cardioSURF Fralin Biomedical Research Institute at Virginia tech Carilion

Cardiovascular Disease and Biomedical Engineering at Purdue/Indiana University Purdue University

LouisVille Undergraduate training Program (LV-UP) University of Louisville - Center for Cardiometabolic Science  

McAllister Heart Institute Summer Undergraduate  Mentoring & Meaningful Experiences in Research University of North Carolina at Chapel Hill

Penn CVI AHA Summer Undergraduate Fellowship University of Pennsylvania

The Oregon Research and InnovatiON (ORION) Undergraduate Internship Program Orgeon Health & Science University

University of Houston - Houston Experience for Advancing Research and Training (UH-HEART) University of Houston Drug Discovery Institute 

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Drug Testing

• Drug testing looks for the presence or absence of specific drugs in a biological sample, such as urine, blood, or hair. Drug testing cannot diagnose a substance use disorder. As a tool in substance use treatment programs , drug testing can monitor a patient’s progress and inform their treatment. Substance use treatment programs should not use drug testing results alone to discharge patients from treatment. Drug testing is also used in workplace and justice settings.
• While multiple test options are available, urine drug screening is most common. An initial urine drug screen can deliver rapid results but can be affected by factors, such as certain medications, that can cause incorrect results (called a false positive or a false negative) . If an initial test is positive, health care providers can order a sensitive and specific confirmatory test. For all testing methods, accurate interpretation may require consultations with specialists such as Medical Review Officers (MRO) and medical toxicologists.
• NIDA supports and conducts research to improve drug testing by investigating more accurate and accessible technologies and applying drug testing in new ways to support individual and public health. NIDA does not administer drug testing programs, assist in interpreting drug test results , or manufacture, regulate, or distribute drug screening products. Learn more about drug testing regulation from the U.S. Food and Drug Administration (FDA) and about workplace drug testing from the Substance Abuse and Mental Health Services Administration (SAMSHA) .

What is a drug test?

A drug test looks for the presence or absence of a drug in a biological sample, such as urine, blood, or hair. Drug tests may also look for drug metabolites in the sample. A drug metabolite is a substance made or used when the body breaks down (or “metabolizes”) a drug.

Drug tests target only specific drugs or drug classes above a predetermined cutoff level. 1  A cutoff level is a point of measurement at or above which a result is considered positive and below which a result is considered negative. For example, in workplace drug testing the federal cutoff level for a cannabis drug test in urine is 50ng/mL. A test result below 50ng/mL will be reported as negative even if the result is above 0. This cutoff level helps to limit false positive s. 2

Drug testing is different than “ drug checking ,” which helps people who use drugs determine which chemicals are found in the substance they intend to take. Drug checking is a type of harm reduction .

What is the difference between a drug screen and a confirmatory drug test?

Usually, drug testing involves a two-step process: an initial drug screen and a confirmatory test.

• Initial drug screens or presumptive drug tests are used to identify possible use of a drug or drug class. These tools are also called point-of-care testing and are useful because they can produce rapid results. Initial urine drug screens use the immunoassay method for analysis, which uses antibodies to detect drugs at the molecular level.
• Confirmatory or definitive tests either verify or refute the result of an initial screen. These tests are more specific, more sensitive, and results take longer because they are sent to a laboratory. These tests use methods called gas chromatography/mass spectrometry or liquid chromatography/mass spectrometry to analyze samples. The results can indicate specific drugs and provide more exact information about how much of a drug is present. 1,3

If an initial drug screen is positive, a second round of more precise confirmatory testing is done to confirm or rule out that positive result.

What substances do drug tests detect?

Drug tests are commonly used to detect five categories of drugs as defined by the federally mandated workplace drug testing guidelines, although health care providers can order additional tests, if needed. 2,3 This list may also change as new drugs enter the drug supply. 4

These drug tests are usually urine tests, though other biological samples can also be used: 2

• Amphetamines, including methamphetamine
• Cannabis (marijuana), which tests for cannabinoid metabolites, including THC metabolites
• Cocaine , which tests for benzoylecgonine, a cocaine metabolite
• Opioids , a class of drugs that includes heroin, synthetic opioids such as fentanyl, and pain relievers like oxycodone (OxyContin ® ), hydrocodone (Vicodin ® ), codeine, and morphine. This category will have separate tests depending on which opioid is being tested. There is currently no drug test that tests for all opioids.
• Phencyclidine (PCP)

Drug tests can also detect additional categories of drugs:

• Barbiturates
• Benzodiazepines
• MDMA/MDA (Ecstasy/Molly)

How is NIDA advancing research on drug testing?

NIDA supports and conducts research to improve drug testing methods by investigating more accurate and accessible technologies and applying drug testing in new ways to support individual and public health. This research includes efforts to develop new highly specific and sensitive tests for urine, breath, and sweat. It also includes the development of innovative technologies such as wearable sensors that can test for drugs in real time.

NIDA also supports the National Drug Early Warning System , which helps collect and share information on emerging drugs that may inform the development of drug tests.

NIDA does not administer drug testing programs, assist in interpreting drug test results , or manufacture, regulate, or distribute drug screening products. Learn more about drug testing regulation from the U.S. Food and Drug Administration (FDA) and about workplace drug testing from the Substance Abuse and Mental Health Services Administration (SAMSHA) .

What is drug testing used for?

Drug testing is used to find out whether a person has used a substance in the recent past. Drug testing can sometimes also detect passive exposure to drugs, such as secondhand smoke or prenatal exposure. The length of time following exposure that a drug can be detected during testing can vary.

Drug testing cannot diagnose a substance use disorder. 2

A drug test may be used for different reasons, including:

• Supporting the clinical aims of substance use disorder treatment .
• A medical assessment , such as during emergency department visits for unintentional poisoning, attempts at self-harm, or environmental exposures. In these cases, point-of-care testing is used to help diagnose and manage patients whose symptoms may be related to drug use. 5,6 Newborns can also be tested for possible prenatal exposure to illicit drugs using urine, blood, meconium (an infant’s first bowl movement), hair, or umbilical cord samples. 7
• Preventing prescription drug misuse. Some health care providers will schedule or order random urine drug testing while prescribing controlled substances, such as opioids, stimulants, and depressants. However, this practice is not standardized. 8,9
• Employment. Employers may require drug testing as part of a drug-free workplace program. Drug testing is required by federal law in some workplaces, including safety and security-sensitive industries like transportation, law enforcement, and national security.
• Legal evidence. Drug testing may be part of a criminal or motor vehicle accident investigation or ordered as part of a court case.
• Athletics. Professional and other athletes are tested for drugs that are used to improve performance (sometimes referred to as “doping”). The U.S. Anti-Doping Agency conducts this testing.
• Recovery residences. Communities of people in recovery from substance use disorders may use drug testing to monitor abstinence of residents. 10  

How are drug tests performed?

Urine is the preferred and most used biological sample for drug testing, as it is available in large amounts, contains higher concentrations of drugs and metabolites than blood, and does not require needles. 11 Urine drug tests are also available during point-of-care, or outside the laboratory (e.g., doctor’s office, hospital, ambulance, at home). 12

Less commonly, drug testing may use blood or serum, oral fluid (saliva), breath, sweat, hair, or fingernails. 1

There are FDA-approved at-home drug tests (urine or saliva) readily available at pharmacies. It is important to follow specific instructions and send a urine sample to a laboratory for confirmation.

How is drug testing used during treatment for substance use disorders?

Urine drug screening can be an important tool for substance use disorder treatment. 13 Health care providers can use urine drug screens to follow a patient’s progress. Test results are used to determine whether dosing adjustments or other treatment interventions are needed. After unexpected results , patients and health care providers can speak openly about treatment and progress to better tailor the treatment to the patient’s needs. 10,13

Federal guidelines for Opioid Treatment Programs require drug testing. Urine drug tests are often administered as part of the intake process to confirm substance use history and as a routine part of therapy. 14

Understanding the limits of urine drug screening and other toxicology testing is an important part of making treatment decisions. Drug testing is never the sole determinant when making patient care decisions. 10

Contingency management is a behavioral therapy that uses motivational incentives including tangible rewards for drug-negative urine specimens. Contingency management has been demonstrated to be highly effective in the treatment of substance use disorders including addiction to stimulants. 15  

What happens if a drug test result is positive during substance use disorder treatment?

If a drug test result is positive during substance use disorder treatment, health care providers may prescribe additional or alternative treatments. Drug test results should not be used as the sole factor when making patient care decisions, including discharge decisions. 10,13 It is best practice for addiction treatment providers to avoid responding punitively to a positive drug test or using it as the basis for expelling someone from treatment. However, actual consequences of a positive drug test during substance use treatment may depend on state laws and the individual program.

Recovery residences (e.g., sober living homes) may also use drug testing to monitor the abstinence of residents, and residents may be expelled on the basis of positive drug tests. However, it is important that expulsion should not prevent or interfere with the individual continuing to receive outpatient addiction treatment. 10

What are the limitations of drug testing?

Urine drug tests do not provide information regarding the length of time since last ingestion, overall duration of use, or state of intoxication. 16

Sometimes urine can be difficult to obtain due to dehydration, urinary retention (the person is unable to empty their bladder), or other reasons. 17

Drug testing can be a useful tool, but it should not be the only tool for making decisions. Drug testing results should be considered alongside a patient’s self-reports, treatment history, psychosocial assessment, physical examination, and a practitioner’s clinical judgment. 2,18

Drug testing can also produce false positives and false negatives.

How accurate are drug tests? Can a drug test result in a false positive or false negative?

All tests have limitations, and false positives or false negatives can occur. 1

A false positive is when a drug test shows the presence of a substance that isn’t there. This can happen during the initial urine drug screening, which uses the immunoassay method (antibodies to detect drugs at the molecular level). Immunoassays are the most commonly available method of testing for drugs in urine. 2 Immunoassays rely on a chemical reaction between an antibody and a drug the test is designed to identify. Sometimes the antibodies can react to other chemicals that are similar to the drug—called cross-reactivity. Cross-reactivity can occur with some over-the-counter medicines, prescription medicines, and certain foods, like poppy seeds. For example, some cough and cold medicines, antidepressants, and antibiotics can cause false positive results. 19,3

A false negative is when a drug test does not show the presence of a substance that is there. This can happen during the initial urine drug screening. A false negative result can happen when the cutoff level used was set too high, so small amounts of the drug or drug metabolites were missed. 2  False negatives can also happen when contaminants are deliberately ingested or added to urine to interfere with a test’s ability to detect a drug’s presence. 20

Laboratory errors can also result in false positives or false negatives.

A confirmatory test can be performed to confirm the initial screening test results. A medical review officer can also interview the patient and review the lab results to help resolve any discrepancies. 1,14

How are drug test results confirmed?

An essential component of any drug testing program is a comprehensive final review of laboratory results. 18 In federally mandated drug testing programs, this role is often filled by a medical review officer, who will review, verify, and interpret positive test results. Medical review officers provide quality assurance and evaluate medical explanations for certain drug test results. The medical review officer should be a licensed physician with a knowledge of substance use disorders. 21

To avoid misinterpreting drug test results, health care providers can use experts in the field. This includes clinical chemists or medical toxicologists at hospitals, clinics, or poison control centers. Expert assistance with toxicology interpretations can improve the accuracy of drug test results. 

Can NIDA assist me with interpreting or disputing the results of a drug screen?

NIDA is a biomedical research organization and does not provide personal medical advice, legal consultation, or medical review services to the public. While NIDA-supported research may inform the development and validation of drug-screening technologies, NIDA does not manufacture, regulate, or distribute laboratory or at-home drug screening products. The U.S. Food and Drug Administration (FDA ) regulates most of these products in the United States. Those with concerns about drug screening results may consider reaching out to the drug-screening program or a qualified health care professional. For more information on workplace drug screening, please visit the Substance Abuse and Mental Health Services Administration (SAMSHA) Division of Workplace Programs website.

Latest from NIDA

What do drug tests really tell us?

NIH and FDA leaders call for more research, lower barriers to improve and implement drug- checking tools amid overdose epidemic

NIH launches harm reduction research network to prevent overdose fatalities

Find more resources on drug testing.

• Learn more about drug test regulation from the U.S. Food and Drug Administration (FDA) .
• Learn more about workplace drug-testing programs from the Substance Abuse and Mental Health Services Administration (SAMHSA) .
• Find basic drug testing information from MedlinePlus , a service of NIH’s National Library of Medicine (NLM).
• Find information about drug testing in child welfare from the National Center on Substance Abuse and Child Welfare . 
• McNeil SE, Chen RJ, Cogburn M. Drug testing . In: StatPearls . StatPearls Publishing; January 16, 2023.
• Center for Substance Abuse Treatment. Clinical drug testing in primary care . Substance Abuse and Mental Health Services Administration. Technical Assistance Publication Series , No. 32 2012. Accessed May 3, 2023
• Moeller KE, Lee KC, Kissack JC. Urine drug screening: practical guide for clinicians . Mayo Clin Proc . 2008;83(1):66-76. doi:10.4065/83.1.66
• Gerona RR, French D. Drug testing in the era of new psychoactive substances . Adv Clin Chem . 2022; 111:217-263. doi:10.1016/bs.acc.2022.08.001
• Mukherji P, Azhar Y, Sharma S. Toxicology screening . StatPearls . Updated August 8, 2022. Accessed May 3, 2023.
• Bhalla A. Bedside point of care toxicology screens in the ED: Utility and pitfalls . Int J Crit Illn Inj Sci . 2014;4(3):257-260. doi:10.4103/2229-5151.141476
• Farst KJ, Valentine JL, Hall RW. Drug testing for newborn exposure to illicit substances in pregnancy: pitfalls and pearls . Int J Pediatr . 2011;2011:951616. doi:10.1155/2011/951616
• Chakravarthy K, Goel A, Jeha GM, Kaye AD, Christo PJ. Review of the Current State of Urine Drug Testing in Chronic Pain: Still Effective as a Clinical Tool and Curbing Abuse, or an Arcane Test? . Curr Pain Headache Rep . 2021;25(2):12. Published 2021 Feb 17. doi:10.1007/s11916-020-00918-z
• Raouf M, Bettinger JJ, Fudin J. A practical guide to urine drug monitoring . Fed Pract . 2018;35(4):38-44.
• Jarvis M, Williams J, Hurford M, et al. Appropriate use of drug testing in clinical addiction medicine . J Addict Med . 2017;11(3):163-173. doi:10.1097/ADM.0000000000000323
• Kapur BM. Drug-testing methods and clinical interpretations of test results . Bull Narc . 1993;45(2):115-154.
• Hadland SE, Levy S. Objective Testing: Urine and Other Drug Tests . Child Adolesc Psychiatr Clin N Am . 2016;25(3):549-565. doi:10.1016/j.chc.2016.02.005
• Center for Substance Abuse Treatment. Substance abuse: Clinical issues in intensive outpatient treatment . Substance Abuse and Mental Health Services Administration. Treatment Improvement Protocol (TIP) Series , No. 47 2006. Accessed May 3, 2023.
• Substance Abuse and Mental Health Services Administration . Federal guidelines for opioid treatment programs . Published January 2015. Accessed May 3, 2023.
• Petry NM. Contingency management: what it is and why psychiatrists should want to use it . Psychiatrist . 2011;35(5):161-163. doi:10.1192/pb.bp.110.031831
• Dobrek L. Lower Urinary Tract Disorders as Adverse Drug Reactions-A Literature Review . Pharmaceuticals (Basel). 2023;16(7):1031. Published 2023 Jul 20. doi:10.3390/ph16071031
• Chua I, Petrides AK, Schiff GD, et al. Provider Misinterpretation, Documentation, and Follow-Up of Definitive Urine Drug Testing Results . J Gen Intern Med . 2020;35(1):283-290. doi:10.1007/s11606-019-05514-5
• Reisfield GM, Teitelbaum SA, Jones JT. Poppy seed consumption may be associated with codeine-only urine drug test results . J Anal Toxicol . 2023;47(2):107-113. doi:10.1093/jat/bkac079
• Kale N. Urine Drug Tests: Ordering and interpreting results . Am Fam Physician . 2019;99(1):33-39.
• Center for Substance Abuse Treatment. Division of Workplace Programs. Medical review officer guidance manual for federal workplace drug testing programs . Substance Abuse and Mental Health Services Administration . 2020. Accessed April 20, 2023.

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StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-.

StatPearls [Internet].

Drug testing.

Shawn E. McNeil ; Richard J. Chen ; Mark Cogburn .

Affiliations

Last Update: July 29, 2023 .

• Continuing Education Activity

Drug testing detects the presence or absence of a drug or its metabolites in a biological sample. This process can be completed in a variety of settings and with a variety of techniques. Despite the drawbacks, drug testing plays an essential role in the clinical setting because clinical examination, patient self-reporting, and collateral reporting will often underestimate the actual incidence of substance use. However, drug testing should always be used with history/physical and psychosocial assessment. This activity describes the process of drug testing, the nuances of drug testing, the interpretation of false positive and false negative results, and the role of the interprofessional team in managing patients who use illicit drugs.

• Identify the function of drug testing.
• Outline the types of biological matrices that can be used for drug testing.
• Describe the issues of concern in regard to drug testing, including issues of false positives and negatives.
• Summarize interprofessional team strategies for improving care coordination and communication to advance the management of patients who abuse drugs and improve outcomes.
• Introduction

Broadly defined, drug testing uses a biological sample to detect the presence or absence of a drug or its metabolites. This process can be completed in a variety of settings and with a variety of techniques. Many drug screening immunoassays were initially designed for use in the workplace as a drug screening tool for employees. As these tests have become cheaper, more readily available, and easier to use, these tests are now standard in many clinical laboratories. Despite their prevalence, many physicians and providers do not understand how these tests function and their associated limitations. [1] [2]  Despite the drawbacks, drug testing plays an essential role in the clinical setting because clinical examination, patient self-reporting, and collateral reporting will often underestimate the actual incidence of substance use. The use of drug screens is also becoming increasingly important in the management of patients with chronic pain and in the treatment of substance use disorders. [3]  

The most commonly tested-for substances are amphetamines, cannabinoids, cocaine, opiates, and phencyclidine (PCP). These drugs are also referred to as the "NIDA five" as these were the five drugs that were recommended for drug screening of federal employees by the National Institute on Drug Abuse (NIDA). This responsibility now falls on the Substance Abuse and Mental Health Services Administration (SAMHSA). There are now expanded drug screens that include testing for oxycodone, methadone, buprenorphine, and fentanyl, among many other drugs.  [4]

There are several biological samples that can be used for testing. These include blood or serum, sweat, hair, oral fluid, nails, and urine. The most commonly used biological sample is urine, as it is non-invasive, and the concentration of a given xenobiotic is generally higher when compared to other samples. This usually results in a higher sensitivity. [3]  Additional considerations include how long a xenobiotic remains detectable in various matrices. It is important to consider these aspects in the context of why testing is being performed.

Immunoassays remain the most common and easily accessible form of testing. More advanced methods, particularly in confirmatory testing, are available and include gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/mass spectrometry (LC/MS). These advanced methods tend to have higher specificity and sensitivity as compared to immunoassays, but are more expensive and require specialized equipment and training. [5]

Although drug testing can be used to confirm the recent use of a substance, it also has a role in the diagnosis, treatment, and monitoring of addiction. As a tool for monitoring, this type of testing has the potential to measure the performance of a patient’s substance use treatment. Urine drug testing (UDT) remains the most common modality for detecting drugs in the human body, and it is based on immunoassay techniques. Clinicians should understand the value of random drug testing as opposed to scheduled testing, particularly in the context of a suspected or established substance use disorder. [6] [7]

There are several factors that need to be considered when choosing a particular drug test. Using a certain matrix or rotating matrices can reduce the chances of sample tampering. There are also times when a certain matrix may not be appropriate (i.e., using a hair sample with chemically treated hair or using directly observed urine testing when a patient has had sexual trauma). There is also often a tradeoff when choosing one test over another. Some tests may be regarded as “presumptive” while others are regarded as “definitive." Presumptive tests will typically give a faster result, which may aid in timely clinical decision-making. However, the specificity and/or sensitivity may be lower compared to a definitive test. There may be times when the patient will dispute the results of a presumptive test, and a more definitive test can then be done to provide clarification. A clinician may consider going directly to definitive testing if there is no reasonable presumptive test or if the results of the testing will have major implications.

An important consideration in drug testing is establishing a predetermined cutoff concentration. This value determines the concentration of a xenobiotic in a specimen that results in a positive test. This threshold should be sufficiently high to prevent false-positive results due to cross-reactivity and variability in the test itself and be low enough to prevent false negatives in those who regularly use the xenobiotic being tested for. The exact cutoff can vary depending on the specific xenobiotic, the immunoassay being used, or the clinical context. [3] [8]

Types of Matrices

Urine testing typically has a detection window of hours to days. It usually takes two hours before a substance can be detected in the urine. Factors like urine pH and fluid intake can have an impact on the results. Urine is the most well-established matrix and is the most commonly used matrix for point-of-care testing (POCT). The detection window can be up to 4 days for some substances. Chronic use can extend this window out to weeks. [9] Although sample tampering may be an issue, clinicians have the option of having observed sample collection in many cases. However, this may not completely remove the possibility of sample tampering. Substances that are likely to be tested for with a urine sample include alcohol, amphetamines, benzodiazepines, opiates/opioids, cocaine, and cannabis.

Blood testing is primarily done in emergency situations and is typically used to detect ethanol levels. The advantage of blood testing is that it allows for a precise level to be assessed. Additionally, testing for drugs of abuse often requires that samples be sent to an outside lab. The detection window is usually one to two days. [9] The downside includes the invasiveness of the test, the need for someone skilled to obtain the sample, and the fact that the sample can be a potential biohazard. 

Breath testing is also primarily used for alcohol detection. More precisely, it allows for the assessment of recent alcohol use. The result is called a breath alcohol concentration or BrAC. The BrAC is often used as an estimate of blood alcohol concentration (BAC). However, on an individual basis, the BrAC can either overestimate or underestimate the blood ethanol level. Research has been focusing on the potential use of breath testing for the detection of cocaine, cannabis, benzodiazepines, amphetamines, opioids, methadone, and buprenorphine. [10] [11]

Oral fluid testing (OFT) generally detects concentration that correlates with plasma concentrations. However, the concentration of orally consumed substances will be higher. Oral testing is more likely to detect parent compounds versus urine testing which relies more heavily on metabolite concentrations. The detection window varies but can be up to 48 hours. [9]

Sweat testing is completed through the use of an absorbent pad that is collected. The results of testing this pad give a cumulative concentration that suggests how much of a substance that person consumed over the entire period that the pad was worn. There can be problems with contamination or incomplete adhesion of the patch to the skin. One benefit of sweat testing is that it gives a detection window of hours to weeks.

Hair, as a matrix for the detection of substances, can provide information on cumulative substance use. Similar to sweat testing, hair testing has a long detection window. Scalp hair has a detection window of three months, while slower-growing body hair (such as pubic or axillary hair) has a detection window of up to 12 months. The results of the hair testing can vary based on the individual in regards to the characteristics of their hair. Hair testing can be used for the detection of cocaine, phencyclidine (PCP), amphetamines, opioids, and 3,4-Methylenedioxymethamphetamine (MDMA). Potential shortcomings of this matrix include price, environmental cross-contamination, and issues during decontamination prior to testing and establishing cut-off values. [12]

Often, contingency management is paired with drug testing in the treatment of addiction, and behavioral incentives are allowed on the basis of a negative result. These incentives (or “reinforcers”) can be vouchers or prizes that are given to encourage the patient to continue their abstinence from a particular substance. The use of POC testing, in particular, makes the implementation of contingency management easier because of the rapid results that can be achieved. [13] [14]

• Issues of Concern

The technologies behind drug testing as well as the clinical application of this technology are rapidly evolving. It is important that clinicians understand the proper use of current methods and stay informed about emerging techniques. One of the biggest challenges facing clinicians is the accurate detection of drugs that have relevance to clinical outcomes. [15]  

As with all testing, false negatives and false positives are a possibility. False negatives are defined as a negative test result despite the presence of a given xenobiotic. A false positive is defined as a positive test result despite no xenobiotic present in a sample. Common false positives are described in the testing of amphetamines and include medications such as selegiline, bupropion, and pseudoephedrine. [16]

False negatives are well described when testing for opioids and benzodiazepines. The opiate screen on the UDT specifically detects morphine. As a result, this screen would not detect synthetic opioids, such as fentanyl and methadone, or other opioids that are structurally dissimilar such as buprenorphine, oxycodone, and hydrocodone. Similarly, the benzodiazepine screen tests for a metabolite, oxazepam. It would be expected to test negative for benzodiazepines such as lorazepam, clonazepam, and alprazolam as these are not metabolized to oxazepam.

Depending on the xenobiotic being tested for, there can be multiple other xenobiotics that can crossreact and cause a false positive result. These are commonly described in testing for amphetamines, PCP, cannabinoids, and methadone. [3] [17] [18]  It is important to consider what medications patients may be taking when a positive result is obtained on presumptive testing. Common over-the-counter medications, such as diphenhydramine and dextromethorphan can result in a positive result on the PCP screen.

The protocols in place when performing drug testing in the workplace vs a clinical setting vary in several important aspects. Confirmatory testing is not standard procedure in the clinical setting, as the results from a presumptive test are often enough to direct clinical decisions. In the workplace, when a presumptive test is positive, it is routinely sent off for confirmatory testing so that an appropriate decision can be made concerning employment. By extension, in workplace testing, the chain of custody is important to maintain the validity of testing. It is not uncommon for results to be disputed, and so maintenance of the chain of custody will make it more difficult to invalidate results due to a procedural problem. [8]

A major concern in testing, particularly in UDT is the possibility of sample tampering. One common method is dilution, either by dilution by adding an adulterant or by increasing fluid intake prior to the test. Common adulterants include household items, such as bleach, laundry detergent, and table salt. Commercial products directed at bypassing UDT also exist, such as UrinAid (glutaraldehyde), Stealth (containing peroxidase and peroxide), Urine Luck (pyridinium chlorochromate), and Klear (potassium nitrite). These products are easily obtained through various internet sources. Synthetic urine is another common adulterant. These adulterants can be used to bypass both presumptive and confirmatory tests. For example, glutaraldehyde is commonly used to create a false negative for cannabinoids. Oxidative additives can react with drug and drug metabolites and make them undetectable with common immunoassays. Fortunately, there have been advancements in laboratory testing to detect common adulterants. [19]

The current drug landscape is continually changing. New synthetic drugs continue to be made and enter the current drug supply. Many of these drugs are structurally unlike any current existing drugs and as a result, are not detectable with current testing. This can make it difficult to determine if someone is using a particular substance. Continued research and development are needed to keep pace with new synthetic drugs and to address continued attempts at test adulteration. [4] [20]

• Clinical Significance

Drug testing can be used to further assess a patient presenting for evaluation or be used in the workplace for employment eligibility.

A positive result on a drug test tells the clinician that the patient had a detectable amount of a substance present during a certain window of time. This result does not typically indicate that impairment is the result of any particular substance or that the patient has a substance use disorder. When considering a positive result, confirmatory testing may be helpful in verifying results in certain situations. As discussed previously, false positives can occur due to cross-reactivity between other substances not being tested for and the immunoassay being used.

A major consideration when using drug testing is regarding the significance of a negative result. Clinicians should bear in mind that a negative result simply means that the particular substance being tested for was not detected. [21] This may mean its level was not sufficient enough to be detected or that use of that substance did not occur during the detection window. A negative result does not rule out the use of a substance or the presence of a substance use disorder. False negatives are not uncommon, particularly if the clinician is not aware of what is being tested for in a given immunoassay. A common example is in the testing of benzodiazepines, where the immunoassay is directed at the detection of oxazepam and is not intended to detect benzodiazepines such as clonazepam or alprazolam. 

It is essential that clinicians understand the testing methodology of various drug testing modalities as well as their associated sensitivity, specificity, and significance of false-negative and false-positive results. 

• Other Issues

Another issue regarding the use of drug testing in the clinical setting is the attitude of some patients that the results of a drug test may be used in a punitive way. It is important that clinicians are forthcoming about how drug testing is being used. Specifically, in the clinical setting, clinicians should make it clear that a drug test will not be used in a punitive fashion and is being used to help improve the care that the patient is receiving.

Another area of concern is the issue of drug testing adolescents. In particular, the American Academy of Pediatrics Committee on Substance Abuse has made it clear that involuntary drug testing of an adolescent with decisional capacity is inappropriate. [18]

• Enhancing Healthcare Team Outcomes

Drug testing is now commonly done in clinical medicine for a variety of reasons. Because of the stigma associated with drug use and positive drug tests, the physician has an important role in setting the non-judgemental tone that may influence a patient's care. It is important that every member of the care team (physicians, nursing, ancillary staff, etc.) understand why drug testing is being performed. In the clinical setting, positive drug test results should not be used for punitive purposes. Instead, the result should be looked at as an opportunity to have a discussion concerning potential drug use in a patient. Finally, random drug testing on every patient is not recommended; it has to be supported by history and a physical exam. Healthcare workers including nurses and pharmacists should be aware of the laws surrounding drug usage, drug test results, and confidentiality laws. [15]

Drug testing in the workplace is vastly different in purpose than in the clinical setting and it is an important tool to identify those who may be working under the influence, as this can be a potential safety concern. It is important that test results are confirmed prior to any sanctions against an employee being made.

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Disclosure: Shawn McNeil declares no relevant financial relationships with ineligible companies.

Disclosure: Richard Chen declares no relevant financial relationships with ineligible companies.

Disclosure: Mark Cogburn declares no relevant financial relationships with ineligible companies.

This book is distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ), which permits others to distribute the work, provided that the article is not altered or used commercially. You are not required to obtain permission to distribute this article, provided that you credit the author and journal.

• Cite this Page McNeil SE, Chen RJ, Cogburn M. Drug Testing. [Updated 2023 Jul 29]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-.

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