Do all drugs show up in hair follicle test
Understanding Do All Drugs Show Up in Hair Follicle Test and Its Detection Benefits
Do all drugs show up in hair follicle test? Hair follicle testing detects many commonly abused drugs over a 90-day period but does not detect all substances. This test identifies drug metabolites embedded in hair shafts, providing a long detection window. Call (877) 731-6362 to schedule or learn more.
Do all drugs show up in hair follicle test?
Hair follicle drug tests detect a wide range of drugs but do not identify every drug. The test analyzes hair samples for drug metabolites that accumulate in the hair shaft after drug use. Commonly detected drugs include cocaine, marijuana (THC), opiates, amphetamines, methamphetamines, phencyclidine (PCP), and some prescription medications.
However, certain drugs may not be reliably detected due to their chemical properties, usage patterns, or low incorporation into hair. This makes hair follicle testing a strong but not all-encompassing method for drug detection.
What all shows up on a hair follicle drug test?
Hair follicle tests typically screen for these drug classes:
The panel selection can vary depending on the requester and laboratory capabilities. AMH Nationwide routes collections through five national lab networks: Quest Diagnostics, LabCorp, Omega Labs, United States Drug Testing Labs, and ExperTox.
How does hair follicle testing detect drugs?
Hair follicle testing detects drugs by identifying their metabolites deposited in the hair shaft from the bloodstream. After drug use, metabolites enter the hair follicle and become trapped within the hair structure as it grows.
This method allows detection of drug use over approximately 90 days, as hair grows about 0.5 inches per month. A standard 1.5-inch hair sample can reveal drug use history for about three months.
Hair testing is not effective for detecting very recent drug use (within a few days) due to the time required for the hair to grow out from the follicle.
Are there drugs that do not show up on hair follicle tests?
Yes. Some drugs either do not incorporate well into hair or are not included in standard test panels. For example, alcohol is not detected by hair follicle drug tests but requires specialized testing of hair for ethyl glucuronide (EtG).
Some synthetic drugs or newer psychoactive substances may not be detected if the test panel does not specifically include them. Additionally, passive exposure rarely causes positive results due to the way hair testing analyzes metabolites internally incorporated into hair.
Testing limitations depend on the laboratory panel and the chemical nature of the drug.
Need Accurate Hair Follicle Drug Testing?
Call (877) 731-6362 to schedule your hair follicle drug test or to speak with a specialist about detection panels and testing procedures.
Who orders hair follicle drug tests and why?
Employers, courts, probation officers, and individuals request hair follicle testing to verify drug abstinence or detect past drug use over extended periods. It is often used when a long detection window is required or when urine testing is insufficient.
Hair testing is useful for safety-sensitive positions and legal cases but is not DOT-regulated for hair. DOT-regulated tests require urine testing under the federally certified urine protocol (49 CFR Part 40).
AMH Nationwide facilitates the lab order and directs the requester to one of 20,000+ nationwide collection sites to ensure proper sample collection.
How is hair follicle testing conducted through AMH Nationwide?
AMH Nationwide provides the lab order and directs the requester or donor to a local collection site. The hair sample is collected close to the scalp to ensure analysis of recent hair growth.
Samples are sent to one of five national lab networks: Quest Diagnostics, LabCorp, Omega Labs, United States Drug Testing Labs, or ExperTox for analysis. Results are reviewed by a certified Medical Review Officer to confirm non-negative findings before reporting.
There is no online ordering. To initiate testing, call (877) 731-6362.
Common Questions
Hair follicle tests detect drug metabolites incorporated into hair over time. A single use may be detected if enough drug is present to deposit metabolites in the hair shaft, but detection depends on dosage, hair growth, and timing.
Hair follicle testing can detect drug use typically 7-10 days after use, covering approximately 90 days of history depending on hair length collected.
Hair color can influence drug binding slightly due to melanin content, but modern testing accounts for this, and it does not prevent accurate detection.
Some prescription drugs, such as certain opiates and benzodiazepines, can be detected if included in the test panel. This depends on the specific panel ordered.
Passive exposure is unlikely to cause a positive result because hair testing detects metabolites formed inside the body, not external contamination.
DOT regulations require urine testing under 49 CFR Part 40 for safety-sensitive roles. Hair follicle testing is used for non-DOT testing purposes.
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.