--- title: "How to read a hair follicle drug test result" description: "Learn how to read a hair follicle drug test result with expert guidance. Understand panels, detection windows, and MRO reviews. Call (877) 731-6362." author: "AMH Nationwide" date: "2026-08-28" tags: ["how to read a hair follicle drug test result", "how to read a hair follicle drug test result | how to read hair follicle drug test results"] canonical: "https://amhnationwide.com/how-to-read-a-hair-follicle-drug-test-result/" last_updated: "2026-08-28" --- # How to read a hair follicle drug test result **By AMH Nationwide** | August 28, 2026 Learn how to read a hair follicle drug test result with expert guidance. Understand panels, detection windows, and MRO reviews. Call (877) 731-6362. --- How to read a hair follicle drug test result involves interpreting the lab report that shows drug presence in hair samples collected and analyzed by accredited labs. Results include detected substances, concentrations, and are reviewed by a certified Medical Review Officer. For detailed assistance, call (877) 731-6362. TEST BASICS ## What is a hair follicle drug test and how are results reported? A hair follicle drug test detects drug metabolites embedded in hair shafts, reflecting drug use over approximately 90 days. The test analyzes a small hair sample collected at a designated site and processed by one of five national lab networks: [Quest Diagnostics](https://www.questdiagnostics.com/), [LabCorp](https://www.labcorp.com/), Omega Labs, United States Drug Testing Labs, or ExperTox. Results are reported as positive or negative for specific drugs or drug classes, often including concentrations measured in picograms per milligram (pg/mg) of hair. The lab report lists each tested substance and its status based on established cutoff levels. Every non-negative result undergoes review by a certified Medical Review Officer (MRO) who verifies the findings and considers any legitimate explanations before finalizing the report. INTERPRETATION ## How do I interpret the different parts of a hair follicle drug test result? A typical hair follicle drug test result includes the following key components: 1. Drug Panel: Lists the specific substances tested, such as THC, cocaine, opiates, amphetamines, and PCP. 2. Result Status: Indicates whether the test is negative, positive, or inconclusive for each substance. 3. Concentration Levels: Shows the amount of drug metabolite detected, usually in picograms per milligram of hair. 4. Cutoff Values: The minimum concentration required to report a positive result, established by [SAMHSA](https://www.samhsa.gov/workplace/drug-testing) or other regulatory bodies. 5. MRO Review Notes: Comments from the Medical Review Officer addressing potential explanations or confirming the result. Drug Panel: substances tested Result Status: positive, negative, or inconclusive Concentration Levels: measured drug amounts Cutoff Values: thresholds for positivity MRO Review: certified expert validation [DETECTION WINDOW](https://amhnationwide.com/hair-follicle-drug-test-detection-window/) ## What is the detection window reflected in hair follicle drug test results? Hair follicle drug tests detect drug use over approximately the past 90 days. This is because drugs and their metabolites incorporate into hair follicles as hair grows, roughly one-half inch per month. The standard collection length is about 1.5 inches of hair, representing a three-month detection window. This long window makes hair testing useful for identifying patterns of drug use rather than recent or one-time use. Unlike [urine](https://amhnationwide.com/urine-drug-testing/) or blood tests, hair tests do not detect drug use within the past few days. They are not suitable for detecting immediate or very recent drug intake. COMMON QUESTIONS ## Can environmental exposure affect how to read hair follicle drug test results? Environmental exposure to drugs, such as passive smoke or contact with drug residues, generally does not cause a positive hair follicle test result because the test detects metabolites incorporated inside the hair shaft, not just surface contamination. Laboratories use washing procedures to remove external contaminants before analysis. The Medical Review Officer also evaluates any claims of environmental contamination during result review to ensure accuracy and fairness. ## Need Help Reading Your Hair Follicle Drug Test Result? Call (877) 731-6362 to speak with AMH Nationwide experts who can explain your test report and guide you through the process. [Call (877) 731-6362](tel:+18777316362)[Contact Us](https://amhnationwide.com/contact-us/) LAB NETWORKS ## Which labs process hair follicle drug tests and how does AMH Nationwide handle results? Hair follicle drug tests ordered through AMH Nationwide are routed to one of five national lab networks: Quest Diagnostics, LabCorp, Omega Labs, United States Drug Testing Labs, or ExperTox. These labs follow SAMHSA-aligned and CAP/CLIA-accredited protocols. AMH Nationwide provides the lab test order and directs you to a nearby collection site. There is no online ordering of tests. After collection, the sample is analyzed and results are reviewed by a certified Medical Review Officer before release. This process ensures reliable, scientifically validated results that employers, courts, and individuals can trust. ORDERING ## How do I get a hair follicle drug test and receive the results? To obtain a hair follicle drug test, contact AMH Nationwide by calling (877) 731-6362. We provide the lab order and direct you to a collection site near you. Collection sites perform the hair sample collection under standardized procedures. The sample is sent to the assigned national lab for analysis. Results are reviewed by a certified Medical Review Officer and then released to the requester. Pricing varies depending on the panel and detection window. Call for a quote and detailed instructions. AMH Reviewed & Maintained By AMH Nationwide Customer Service AMH Nationwide is BBB A+ accredited and routes every order through Quest Diagnostics, LabCorp, Omega Labs, United States Drug Testing Labs, or ExperTox, all of which use multiple lab certification agencies and standards such as SAMHSA-aligned laboratory protocols, the ANSI National Accreditation Board for forensic testing and calibration, the College of American Pathologists (CAP), and Clinical Laboratory Improvement Amendments (CLIA). Every non-negative screen is reviewed by a certified Medical Review Officer as part of standard processing before a result is released, and chain-of-custody documentation is maintained on every collection. This page does not constitute medical or legal advice. **Last updated:** July 2026 You May Also Need [Nail Drug TestingNo head or body hair available? A 5-panel fingernail test covers a similar look-back window.Learn more →](https://amhnationwide.com/5-panel-fingernail-drug-test/)[ChildGuard: Environmental ExposureConcerned about a child or loved one? ChildGuard screens for exposure to drugs in their environment.Learn more →](https://amhnationwide.com/5-panel-hair-drug-test-environmental-exposure-childguard/)[Shorten the Detection WindowShortened options like 30 and 60 day hair panels are also available, useful when a urine test’s 1-3 day window is too short.Learn more →](https://amhnationwide.com/30-day-hair-drug-test/)[Hair ETG Alcohol TestAlso need alcohol testing? The hair ETG test screens for alcohol use, and can be added to the same collection.Learn more →](https://amhnationwide.com/etg-and-peth/) Frequently Asked Questions ## Common Questions Results typically take 3 to 5 business days after the lab receives the hair sample. The Medical Review Officer review may add additional time before final results are released. Hair follicle tests reflect drug use over about 90 days, so they can detect one-time use if enough drug metabolite is incorporated. However, very low or infrequent use may sometimes go undetected. Yes, when processed by accredited labs and reviewed by a certified Medical Review Officer, hair follicle drug test results are highly reliable and accepted by employers and legal entities. Certain hair treatments like bleaching or dyeing may reduce drug metabolite concentrations but do not guarantee a negative result. Labs account for such factors during analysis. No, DOT-regulated safety-sensitive testing requires the federally certified urine protocol under [49 CFR Part 40](https://www.transportation.gov/odapc/part40). Hair testing is used for non-DOT roles. Inconclusive results may prompt additional testing or review by the Medical Review Officer to determine if the sample is valid or if re-collection is necessary. Sources • [SAMHSA – Mandatory Guidelines for Federal Workplace Drug Testing Programs](https://www.samhsa.gov/workplace/drug-testing) • [U.S. DOT – 49 CFR Part 40 – Procedures for Transportation Workplace Drug and Alcohol Testing Programs](https://www.transportation.gov/odapc/part40) • [CDC – National Center for Health Statistics – Drug Use FastStats](https://www.cdc.gov/nchs/fastats/drug-use.htm) • [Quest Diagnostics – Employer Solutions, Hair Testing Methodology](https://www.questdiagnostics.com/) • [LabCorp – Occupational Testing Services](https://www.labcorp.com/) ## Ready to get started? AMH Nationwide provides the lab order and arranges collection nationwide. Every non-negative result reviewed by a certified Medical Review Officer. Call (877) 731-6362 or contact us. [Call (877) 731-6362](tel:+18777316362)[Contact Us](https://amhnationwide.com/contact-us/) --- **Need a drug, alcohol, HIV or STD test?** AMH Nationwide is a national lab testing agency operating since 2004, with more than 20,000 collection sites across the United States. Hair, urine, fingernail and blood testing, panels from 5 through 19, for individuals and employers. - Call: (877) 731-6377 - Find a collection site: https://amhnationwide.com/locations/ - Full page: https://amhnationwide.com/how-to-read-a-hair-follicle-drug-test-result/