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How Does a Lab Become SAMHSA Certified (and Why It Matters)?

If you’ve ever wondered how a laboratory becomes SAMHSA certified or why this certification is so important, you’re not alone. Employers, collectors, and even other labs often ask what goes into the process and what benefits come with it. Let’s break it down in simple terms.

What Is SAMHSA Certification?

SAMHSA stands for the Substance Abuse and Mental Health Services Administration, and it oversees the National Laboratory Certification Program (NLCP). For a lab, earning this certification means they meet the highest standards set by the federal government for workplace drug testing.

In short: if a lab wants to handle DOT-regulated drug tests (for trucking, aviation, rail, transit, pipeline, or maritime industries), they must be SAMHSA certified.

How a Lab Becomes SAMHSA Certified

Getting certified isn’t just a quick application—it’s a multi-step process designed to ensure accuracy, reliability, and integrity. Here’s how it works:

Apply to the NLCP

The lab submits an application agreeing to follow all HHS Mandatory Guidelines and DOT drug testing rules under 49 CFR Part 40.

On-Site Inspection

Federal inspectors visit the lab to check equipment, security, staff qualifications, and chain-of-custody procedures.

Proficiency Testing (Blind Samples)

The lab must correctly test and report on “mystery” samples sent by the NLCP. These samples cover both negative and positive results across multiple drug classes.

Quality Control Review

Everything from staff training to specimen handling is evaluated to make sure the lab can maintain consistent accuracy.

Certification Approval

Once a lab passes all requirements, it’s officially listed as an HHS/SAMHSA Certified Laboratory in the Federal Register and on the SAMHSA website. Certification is renewed annually with ongoing inspections and proficiency testing.

Why Being SAMHSA Certified Is a Big Deal

So, why go through all that? Here are the key benefits of SAMHSA certification:

• ✅ DOT Testing Authority – Only SAMHSA-certified labs can process Department of Transportation drug tests.
• ✅ Trust and Credibility – Employers and agencies know certified labs meet the highest forensic standards.
• ✅ Legal Defensibility – Test results stand up in federal and many state courts.
• ✅ More Business Opportunities – Many employers and government contracts require a SAMHSA-certified lab.
• ✅ Ongoing Oversight – Regular proficiency tests and inspections keep quality consistent year-round.

Final Thoughts

Becoming a SAMHSA certified laboratory is a challenging process, but the payoff is huge. Not only does it open the door to DOT-regulated testing, but it also builds trust with employers, government agencies, and courts nationwide.

If you’re an employer choosing a testing provider, always confirm they’re on the official SAMHSA certified lab list. That way, you know your program meets federal standards and your results are reliable and defensible.

How does a laboratory analyze a drug test

To analyze a drug test, a laboratory uses a two-step process to ensure accuracy. An initial, rapid immunoassay screen determines if a sample is presumptively positive for a class of drugs. If it is, a more precise confirmatory test using mass spectrometry is performed to identify the specific drug or its metabolites.

Step 1: Initial screening (Immunoassay) when test first arrives.

The first step is a cost-effective and rapid test that provides a simple negative or presumptive positive result.

Methodology: Immunoassays use antibodies that bind to specific drugs or their metabolites in a biological sample (such as urine). A cutoff level is used to determine whether the result is negative or positive.

Limitations: Immunoassays can produce false positives due to cross-reactivity with other substances that have a similar chemical structure. For example, certain over-the-counter medications, foods like poppy seeds, or prescription drugs can trigger a presumptive positive result.

Step 2: Confirmatory testing (Mass spectrometry)

If the initial screen is presumptively positive, the lab performs a more sensitive and specific confirmatory test to eliminate any false positives. The sample is not simply retested, but is analyzed using a different, more powerful methodology.

Methodology: The gold standard for confirmatory testing is gas chromatography/mass spectrometry (GC/MS) or liquid chromatography/tandem mass spectrometry (LC/MS/MS).

• 1. Chromatography: First, the sample is separated into its individual components. A liquid or gas stream carries the sample through a column, separating the different compounds based on their chemical and physical properties.
• 2. Mass spectrometry: As each separated compound exits the column, it is bombarded with electrons and ionized. A mass spectrometer then separates and measures these ions based on their unique mass-to-charge ratio.
• 3. Analysis: The process creates a unique "fingerprint" or mass spectrum for each compound, which the lab can compare to a known reference library to definitively identify the substance.

Key quality control measures

To ensure the integrity of the results, laboratories follow strict quality control procedures at every stage.

• Chain of custody: From the moment a sample is collected until it is disposed of, a "chain of custody" is meticulously documented. This legally defensible paper trail prevents tampering and ensures the sample's integrity throughout the testing process.
• Adulteration checks: To detect tampering, labs routinely test for signs of adulteration in urine samples. They check for:
  • Temperature: The sample's temperature is checked immediately after collection. If it is outside a specific range, substitution may have occurred.
  • pH and creatinine: Labs measure the pH and creatinine levels to ensure the sample is not excessively diluted with water or other substances.
  • Adulterants: Chemical markers are used to check for commercial adulterants that are sold specifically to interfere with drug tests.
• Medical review: After testing, the results are reviewed by a Medical Review Officer (MRO), a licensed physician. The MRO examines the results alongside any medical explanations the donor might have for a positive result, such as a valid prescription.

At Accredited Drug Testing, we offer a full range of professional drug and alcohol testing services designed to meet the needs of employers, individuals, legal professionals, and government agencies. With testing locations nationwide, we provide convenient access to reliable, certified testing, whether you require a pre-employment screening, random drug test, DOT-compliant test, or court-ordered service.

Our services include DOT and non-DOT drug testing, alcohol testing, hair follicle testing, EtG alcohol screens, and lab-based urine testing, all performed in accordance with federal and industry standards. We are experienced in meeting the requirements of the Department of Transportation (DOT), including FMCSA, FAA, PHMSA, FTA, and FRA regulations. We also provide consortium enrollment, random selection programs, and supervisor training for workplace compliance.

Accredited Drug Testing takes pride in delivering fast, accurate results and exceptional customer service. All tests are processed by SAMHSA-certified laboratories, and we offer Medical Review Officer (MRO) verification when needed. Whether you're an employer looking to maintain a safe, drug-free workplace or an individual in need of testing for personal or legal reasons, our team is here to help you every step of the way.

Mobile/On-Site Drug Testing

If you're an employer needing to test 25 or more employees and looking to save time and money, we offer mobile on-site drug testing where we come to you. Call us today for more information.

Nationwide Drug Resources

SAMHSA National Helpline
Free 24/7 helpline for treatment referrals and mental health support.

FindTreatment.gov
Search nationwide for treatment centers by zip code or city name.

USA.gov – Substance Abuse Help
Official resource for addiction help, hotlines, and recovery info.

DEA Recovery Resources
Federal site offering addiction education and treatment resources.

NIDA – Recovery Resources
Research-based info and tools for recovery from drug dependence.

CDC – Treatment of Substance Use Disorders
CDC page with overdose prevention and addiction treatment info.

National Center on Substance Abuse and Child Welfare
Support for families managing addiction and child welfare issues.

NASADAD – Federal Resources
Links to national programs focused on drug abuse and recovery.

Addiction Related Resources
Directory of national addiction treatment and prevention links.

Narcotics Anonymous (NA)
Peer support meetings for those recovering from drug addiction.

SMART Recovery
Group recovery program based on science and self-empowerment.

Recovered
Find rehab centers, addiction guides, and recovery assistance.

At Accredited Drug Testing, we offer a full range of professional drug and alcohol testing services designed to meet the needs of employers, individuals, legal professionals, and government agencies. With testing locations nationwide, we provide convenient access to reliable, certified testing, whether you require a pre-employment screening, random drug test, DOT-compliant test, or court-ordered service.

Our services include DOT and non-DOT drug testing, alcohol testing, hair follicle testing, EtG alcohol screens, and lab-based urine testing, all performed in accordance with federal and industry standards. We are experienced in meeting the requirements of the Department of Transportation (DOT), including FMCSA, FAA, PHMSA, FTA, and FRA regulations. We also provide consortium enrollment, random selection programs, and supervisor training for workplace compliance.

Accredited Drug Testing takes pride in delivering fast, accurate results and exceptional customer service. All tests are processed by SAMHSA-certified laboratories, and we offer Medical Review Officer (MRO) verification when needed. Whether you're an employer looking to maintain a safe, drug-free workplace or an individual in need of testing for personal or legal reasons, our team is here to help you every step of the way.

How does the body eliminate Drugs

Drug elimination is the sum of the processes of removing an administered drug from the body. In the pharmacokinetic ADME scheme (absorption, distribution, metabolism, and excretion), it is frequently considered to encompass both metabolism and excretion. Hydrophobic drugs, to be excreted, must undergo metabolic modification making them more polar. Hydrophilic drugs, on the other hand, can undergo excretion directly, without the need for metabolic changes to their molecular structures.

Although many sites of metabolism and excretion exist, the chief organ of metabolism is the liver, while the organ primarily tasked with excretion is the kidney. Any significant dysfunction in either organ can result in the accumulation of the drug or its metabolites in toxic concentrations.

A variety of other factors impact elimination — intrinsic drug properties, such as polarity, size, or pKa. Also other factors include genetic variation among individuals, disease states affecting other organs, and pathways involved in the way the drug distributes through the body, such as first-pass metabolism.

Issues of Concern

Drug elimination is the removal of an administered drug from the body. It is accomplished in two ways, either by excretion of an unmetabolized drug in its intact form or by metabolic biotransformation followed by excretion. While excretion is primarily carried out by the kidneys, other organ systems are involved as well. Similarly, the liver is the primary site of biotransformation, yet extrahepatic metabolism takes place in a variety of organ systems affecting multiple drugs.

Given the multiple organ systems and the variety of metabolic transformations present, drug elimination can entail a significant degree of complexity. Hydrophilic drugs are typically directly excreted by the kidneys, while hydrophobic drugs undergo biotransformation before excretion. The purpose here is twofold – biotransformation serves both detoxify the exogenous substances as well as to increase their hydrophilicity, ensuring their elimination via the kidneys.

Two broad metabolic pathways of hepatic drug transformation exist. Phase I is the direct modification of the target molecule, whereas phase II entails conjugation of the target to a polar molecule of low molecular weight. Phase I prepare the drug to enter phase II, but single-phase metabolism also exists.

Phase I involves oxidation, reduction, and hydrolysis of the exogenous molecule. These reactions are accomplished by hepatic microsomal enzymes, which reside in the smooth endoplasmic reticulum of the hepatocytes. Best known among them is the cytochrome P450 system, whose enzymes are predominantly involved in oxidative metabolism. Within the cytochrome P450 family (CYP), the enzyme responsible for the metabolism of more than 50% of existing drugs is the CYP3A4. Its activity encompasses various classes of medications, including opioids, immunosuppressants, antihistamines, and benzodiazepines. The enzymes can also be induced or inhibited by a variety of substances they interact with, including pharmaceuticals. The increase in metabolic activity with CYP induction results in a diminished activity of drugs targeted by that particular isoform. Conversely, CYP inhibition will result in increased drug plasma concentration, potentially leading toxicity. The CYP3A4 is induced by phenytoin, phenobarbital, and St. John's wort, while diltiazem, erythromycin, and grapefruit inhibit it. Caution is, therefore, necessary when administering CYP3A4-metabolized drugs in the presence of any of the inhibitors or inducers.

Phase II consists of covalent bonding of polar groups to nonpolar molecules to render them water-soluble and allow renal or biliary excretion. Target molecules enter phase II directly or via initial processing through phase I. A variety of polar adjuncts is transferred, including amino acids, glucuronic acid, glutathione, acetate, and sulfate. Glucuronidation is one of the major pathways of phase II biotransformation. The UDP-glucuronosyltransferase (UGT) enzyme family performs this activity. Typically, glucuronide derivatives possess less or no activity of the original drug, but in some cases, pharmacologically active compounds result. Morphine-6-glucuronide is a phase II metabolite of morphine with significant analgesic activity. As with the CYP enzymes, inducers, and inhibitors of phase II, enzymes exist and may influence the efficacy of drugs that rely on conjugation before excretion.

The first-pass effect is a feature of hepatic metabolism that also plays a role in the elimination of multiple drugs. Here, the enteric consumed drugs are exposed directly to the liver via the portal vein, where they undergo biotransformation before entering the systemic circulation. This activity reduces the bioavailability and needs to be factored into the dose administered to the patient. Intravenously administered drugs are not subject to the first-pass effect.

Extrahepatic drug metabolism takes place in the GI tract, kidneys, lungs, plasma, and skin.

Renal excretion completes the process of elimination that begins in the liver. Polar drugs or their metabolites get filtered in the kidneys and typically do not undergo reabsorption. They subsequently get excreted in the urine. Urinary pH has a significant impact on excretion, as drug ionization changes depending on the alkaline or acidic environment. Increased excretion occurs with weakly acidic drugs in basic urine and weakly basic drugs in acidic urine.

Excretion in the bile is another significant form of drug elimination. The liver can actively secrete ionized drugs with a molecular weight greater than 300 g/mol into bile, from where they reach the digestive tract and are either eliminated in feces or reabsorbed as part of the enterohepatic cycle.

Other pathways of excretion include the lungs, breast milk, sweat, saliva, and tears

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