How Do You Clean Your Hair for a Drug Test with Reliable Lab Testing

What is a hair follicle drug test and how does it work?

A hair follicle drug test detects drug metabolites deposited in hair shafts from the bloodstream. It analyzes a small hair sample, usually from the scalp, to identify drug use typically within the past 90 days. This test is commonly ordered by employers, courts, and probation agencies due to its longer detection window compared to urine or saliva tests.

The testing process involves collecting about 1.5 inches of hair close to the scalp, representing approximately 90 days of growth. The sample is sent to one of AMH Nationwide’s five national lab partners—Quest Diagnostics, LabCorp, Omega Labs, United States Drug Testing Labs, or ExperTox—for analysis. Every non-negative result undergoes review by a certified Medical Review Officer to ensure accuracy and interpret findings.

Can cleaning your hair help you pass a hair drug test?

Cleaning your hair before a drug test does not reliably remove drug metabolites embedded deep within the hair cortex. Common shampoos or home remedies cannot penetrate the hair shaft to erase drug evidence. Laboratories use highly sensitive chemical analysis techniques that detect drug traces despite surface cleaning.

Attempts to ‘clean’ hair may reduce surface contamination but do not eliminate metabolites incorporated during hair growth. Consequently, hair drug tests are considered difficult to adulterate or beat by cleaning. Laboratories also test for markers of tampering or dilution.

How long do drugs stay detectable in hair?

Drugs are typically detectable in hair for up to 90 days after use, depending on hair length and growth rate. Hair grows approximately half an inch per month, so a 1.5 inch sample reflects about three months of drug history.

Because the test analyzes incorporated metabolites within the hair shaft rather than external deposits, detection windows are longer than urine or saliva tests. This makes hair follicle testing useful for assessing long-term drug use patterns rather than recent use.

What happens to hair samples at the lab?

At AMH Nationwide, hair samples are routed to one of five national lab networks: Quest Diagnostics, LabCorp, Omega Labs, United States Drug Testing Labs, or ExperTox. These labs perform screening and confirmatory testing using advanced techniques such as immunoassay and gas chromatography-mass spectrometry (GC-MS).

Samples undergo careful preparation to extract drug metabolites from the hair matrix. Testing includes quality controls and checks for adulteration. Any non-negative findings are reviewed by a certified Medical Review Officer to verify results and consider any medical explanations before reporting.

How do I get a hair follicle drug test with AMH Nationwide?

AMH Nationwide provides the laboratory order and directs you to a nearby collection site from our network of over 20,000 nationwide. There is no online ordering for hair drug tests; all testing requires contacting us directly.

To arrange testing, call (877) 731-6362. We will assist with scheduling your hair collection appointment. Collection sites follow strict chain-of-custody procedures to ensure sample integrity. Results are typically available within several days after collection.

Is hair testing used for DOT-regulated drug testing?

Hair follicle drug testing is not approved for DOT-regulated safety-sensitive employee testing. The Department of Transportation requires federally certified urine drug testing under 49 CFR Part 40 for safety-sensitive roles.

Hair testing is sometimes used for non-DOT roles or follow-up testing but does not replace required urine tests for DOT compliance. AMH Nationwide ensures all DOT testing follows federal protocols with certified urine collections.

Common Questions