--- title: "How long is cocaine in hair" description: "Learn how long cocaine is in hair with reliable lab testing. Hair tests detect use for months. Call AMH Nationwide for testing info. Call (877) 731-6362." author: "AMH Nationwide" date: "2026-08-28" tags: ["how long is cocaine in hair"] canonical: "https://amhnationwide.com/how-long-is-cocaine-in-hair/" last_updated: "2026-08-28" --- # How long is cocaine in hair **By AMH Nationwide** | August 28, 2026 Learn how long cocaine is in hair with reliable lab testing. Hair tests detect use for months. Call AMH Nationwide for testing info. Call (877) 731-6362. --- How long is cocaine in hair depends on hair length but typically up to 90 days or more, as hair testing detects cocaine use over several months. Hair tests provide a longer detection window than urine or blood tests. AMH Nationwide uses five national lab networks to ensure accurate results. Call (877) 731-6362. [DETECTION WINDOW](https://amhnationwide.com/hair-follicle-drug-test-detection-window/) ## How long is cocaine detectable in hair samples? Cocaine is detectable in hair for approximately 90 days or longer, depending on hair length and growth rate. Hair testing offers a longer detection window than [urine](https://amhnationwide.com/urine-drug-testing/) or blood tests, which typically detect cocaine for only a few days. Hair grows about half an inch per month, so a standard 1.5-inch hair sample generally reflects cocaine use over the past 90 days. Longer hair samples can extend this detection window proportionally. Typical detection window: up to 90 days Hair growth rate: about 0.5 inches per month Longer hair samples provide longer detection periods TESTING PROCESS ## How does AMH Nationwide process hair cocaine tests? AMH Nationwide routes hair cocaine tests through five national lab networks: [Quest Diagnostics](https://www.questdiagnostics.com/), [LabCorp](https://www.labcorp.com/), Omega Labs, United States Drug Testing Labs, and ExperTox. This ensures standardized and reliable testing. The hair sample is collected at a designated collection site and sent to the lab for analysis. Every non-negative result is reviewed by a certified Medical Review Officer to confirm accuracy and rule out false positives. TEST TYPES ## Who typically orders hair cocaine testing and why? Hair cocaine testing is commonly ordered by employers, courts, [probation](https://amhnationwide.com/hair-follicle-drug-test-probation/) agencies, and individuals for long-term drug use detection. It is especially useful when a longer detection window than urine or blood testing is required. Because hair testing detects cocaine use over months, it is not suitable for detecting very recent use, but it is preferred for monitoring compliance or past exposure. TEST LIMITATIONS ## Can hair cocaine tests detect one-time or passive exposure? Hair cocaine tests can detect one-time use if sufficient drug metabolites have incorporated into the hair shaft, but low-level or single exposures may be harder to confirm. Passive exposure to cocaine smoke or contact is unlikely to produce a positive hair test result because the testing specifically identifies metabolites formed inside the body, not external contamination. ## Need Accurate Hair Cocaine Testing? Contact AMH Nationwide to arrange hair cocaine testing through our extensive network of collection sites and national labs. Call (877) 731-6362 for guidance and scheduling. [Call (877) 731-6362](tel:+18777316362)[Contact Us](https://amhnationwide.com/contact-us/) DOT TESTING ## Is hair cocaine testing used for DOT-regulated safety-sensitive positions? No, the Department of Transportation (DOT) mandates urine testing following the federally certified protocol under [49 CFR Part 40](https://www.transportation.gov/odapc/part40) for safety-sensitive roles. Hair testing is not accepted for DOT drug testing. Hair cocaine testing is used primarily for non-DOT roles where longer detection windows are required. TEST RELIABILITY ## Can hair cocaine tests be beaten or produce false positives? Hair cocaine tests are highly reliable when performed by accredited labs through AMH Nationwide. The presence of cocaine metabolites in hair is a strong indicator of use. Attempts to evade or adulterate hair samples are difficult due to the nature of hair growth and testing protocols. All non-negative results undergo Medical Review Officer evaluation to reduce false positives. 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](https://www.samhsa.gov/workplace/drug-testing)-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 Cocaine use can typically be detected in hair samples up to 90 days or more, depending on hair length and growth. Longer hair samples may reveal use over a longer period. Hair testing does not detect very recent cocaine use because it takes time for hair to grow and incorporate drug metabolites. Urine or blood tests are better for recent use. Passive exposure is unlikely to cause a positive hair cocaine test since the test detects metabolites formed inside the body, not external contamination. No, DOT requires urine testing under federally certified protocols. Hair testing is not accepted for DOT safety-sensitive positions. All non-negative hair cocaine test results are reviewed by a certified Medical Review Officer to confirm accuracy and rule out false positives. You must contact AMH Nationwide by phone at (877) 731-6362 to schedule testing at a collection site. AMH directs the process and routes samples to national labs. 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-long-is-cocaine-in-hair/