How far back can a hair follicle go
How Far Back Can a Hair Follicle Go in Drug Testing for Reliable Results
How far back can a hair follicle go in drug testing? Hair follicle tests typically detect drug use within the past 90 days by analyzing hair segments. This method offers a longer detection window than urine or saliva tests. AMH Nationwide coordinates collections at over 20,000 sites with certified Medical Review Officer review. Call (877) 731-6362.
How far back can a hair follicle go for drug detection?
Hair follicle drug tests can detect drug use up to approximately 90 days prior to collection. This is because hair grows about half an inch per month, and labs typically analyze a 1.5-inch segment closest to the scalp.
Unlike urine or saliva tests that detect recent use within days, hair testing provides a longer detection window. This makes it useful for employers, courts, and probation agencies seeking a more comprehensive drug history.
How is the hair follicle collected and tested?
AMH Nationwide directs the requester to a collection site from its network of five national labs: Quest Diagnostics, LabCorp, Omega Labs, United States Drug Testing Labs, and ExperTox. The collector cuts a small hair sample close to the scalp.
The sample is then sent to the lab for analysis. Every non-negative result undergoes review by a certified Medical Review Officer (MRO) to ensure accuracy and interpret medical explanations.
What are the limitations of hair follicle testing?
While hair follicle testing has a longer detection window, it does not detect very recent drug use within the past 7-10 days, as it takes time for drugs to incorporate into hair.
Hair treatments like bleaching or dyeing can sometimes affect results but do not guarantee a false negative. External contamination is addressed by lab washing protocols.
Detection windows vary by drug type and individual factors such as hair growth rate.
Who typically orders hair follicle drug tests?
Hair follicle tests are commonly used by employers for pre-employment and random drug screening when a longer history is desired.
Courts and probation agencies may order hair testing to monitor compliance with substance use restrictions.
Individuals seeking comprehensive drug history verification may also request hair follicle analysis through AMH Nationwide.
Schedule Your Hair Follicle Drug Test Today
To learn more about how far back a hair follicle can go in drug detection or to arrange testing, call (877) 731-6362. Our team will guide you through the process and direct you to a nearby collection site.
How does hair follicle testing compare to other drug tests?
| Test Type | Detection Window |
|---|---|
| Hair Follicle | Up to 90 days |
| Urine | 1-4 days typical |
| Saliva | 1-3 days |
| Blood | Hours to 1-2 days |
Hair follicle testing provides the longest detection window among common drug tests. However, it is not used for Department of Transportation (DOT) safety-sensitive testing, which requires federally certified urine testing under 49 CFR Part 40.
How do I arrange a hair follicle drug test with AMH Nationwide?
AMH Nationwide does not offer online ordering. To arrange a hair follicle drug test, call (877) 731-6362 to discuss your testing needs and receive a lab order.
You will be directed to one of our nationwide collection sites affiliated with Quest Diagnostics, LabCorp, Omega Labs, United States Drug Testing Labs, or ExperTox for sample collection.
Pricing varies by test panel and detection window. Contact us for a personalized quote.
Common Questions
Hair testing typically analyzes the most recent 1.5 inches of hair, reflecting about 90 days of growth. Testing beyond 90 days is uncommon because older hair is not usually collected or tested.
Hair color can influence drug incorporation slightly, but labs account for this variability. Testing is reliable across hair types and colors.
Labs use washing procedures to remove external contamination, minimizing false positives from passive exposure.
No. DOT regulations require federally certified urine testing under 49 CFR Part 40. Hair testing is for non-DOT roles.
Results typically take 3 to 5 business days after sample collection, including MRO review of non-negative results.
Hair follicle tests can detect many common drugs, including marijuana, cocaine, opiates, amphetamines, and PCP. Specific panels vary by request.
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.