How long do drugs last in hair
How Long Do Drugs Last in Hair for Reliable Drug Testing Results
How long do drugs last in hair depends on the type of drug and hair growth, but typically drugs remain detectable in a hair follicle test for up to 90 days. Hair testing provides a longer detection window compared to urine or saliva tests. AMH Nationwide uses five national lab networks for accurate results. Call (877) 731-6362.
How long do drugs last in hair follicle tests?
Drugs last in hair follicle tests generally for up to 90 days after use. This is because drugs and their metabolites are deposited into the hair shaft from the bloodstream as hair grows, preserving a record of drug use over time.
Hair grows at an average rate of about 0.5 inches per month. Standard hair follicle testing analyzes approximately 1.5 inches of hair closest to the scalp, representing about three months of drug use history.
This extended detection period makes hair follicle tests useful for employers, courts, and probation agencies needing to verify longer-term drug use patterns.
What is involved in a hair follicle drug test?
A hair follicle drug test involves collecting a small sample of hair close to the scalp, usually from the crown or back of the head. The sample is then sent to one of five national lab networks AMH Nationwide uses: Quest Diagnostics, LabCorp, Omega Labs, United States Drug Testing Labs, and ExperTox.
The labs analyze the hair for specific drug metabolites. Any non-negative results are reviewed by a certified Medical Review Officer (MRO) to confirm accuracy and rule out legitimate medical explanations.
AMH Nationwide coordinates the lab order and directs requesters to collection sites. There is no online ordering available. Call (877) 731-6362 for assistance.
Which drugs can be detected in hair and for how long?
Hair follicle tests can detect a range of commonly abused drugs, each with a similar detection window of up to 90 days. Detection depends on the drug’s incorporation into the hair and the length of hair tested.
Because hair testing detects metabolites embedded in the hair shaft, it does not detect very recent use within the past 5-7 days due to the time needed for hair growth.
Can hair follicle drug tests detect one-time or passive drug exposure?
Hair follicle tests are designed to detect repeated or chronic drug use. One-time use may be detected if the hair sample analyzed includes the growth period after the drug was used, but very recent use may not show up immediately.
Passive exposure to drugs such as marijuana smoke is unlikely to produce a positive hair test result because the test detects metabolites incorporated internally, not external contamination.
The reliability of hair testing for long-term drug use makes it a preferred method for many employers and legal agencies.
Need Accurate Hair Follicle Drug Testing?
Call AMH Nationwide at (877) 731-6362 to arrange your hair follicle drug test with labs trusted for nationwide coverage and reliable results.
How does hair testing differ for DOT-regulated safety-sensitive employees?
DOT-regulated drug testing requires urine tests following the federally certified protocol under 49 CFR Part 40. Hair follicle tests are not accepted for DOT safety-sensitive positions.
However, hair follicle drug tests are available for non-DOT roles and provide a longer detection window for employers seeking extended drug use history.
AMH Nationwide ensures all DOT testing meets federal requirements and directs clients accordingly.
How do I get a hair follicle drug test through AMH Nationwide?
AMH Nationwide provides the lab order and directs you to one of over 20,000 collection sites nationwide. There is no online ordering for hair follicle drug tests.
To arrange a test, call (877) 731-6362 to speak with a representative who will assist with lab selection and scheduling.
Pricing varies depending on the drug panel and detection window required. Call for a quote.
Results are reviewed by a certified Medical Review Officer to ensure accuracy and confidentiality.
Common Questions
Hair follicle testing typically detects drugs about 5 to 7 days after use because it takes time for hair containing drug metabolites to grow above the scalp.
Standard hair follicle tests analyze approximately 1.5 inches of hair representing about 90 days. Longer detection is possible with longer hair, but standard tests usually focus on the most recent 90 days.
Hair color and type can influence drug incorporation, but labs account for these variables. Testing protocols are designed to provide reliable results across diverse hair types.
Hair follicle tests primarily detect drugs, not alcohol. There are specific tests for alcohol metabolites, but standard hair drug tests do not measure alcohol consumption.
Hair follicle testing detects drug metabolites incorporated into the hair shaft, making it difficult to alter results. Laboratories use strict protocols to prevent tampering and verify sample integrity.
All non-negative hair follicle drug test results are reviewed by a certified Medical Review Officer who evaluates the findings and may contact the individual for medical explanations before confirming results.
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.