90-Day Drug Use Detection: Hair Follicle Test (2024)

FAQs

Can hair follicle test go past 90 days? ›

Hair drug tests have the longest detection period, and can typically detect drug use for up to 90 days. Depending on the drugs used, a hair sample can sometimes help determine when drug use occurred and whether it's been discontinued.

Hair Follicle Drug Testing FAQ

In general, the detection time is longest in hair, followed by urine and oral fluid. Drugs in hair may be detectable for approximately 90 days, whereas drugs in urine are generally detectable for one to seven days or longer in chronic users and in oral fluid from five to 48 hours.

Hair follicle tests can detect drug use for up to 3 months before testing, using hair samples that come from a person's scalp. Urine tests can detect more recent drug use, while hair follicle tests can identify regular, long-term drug use.

The hair test is regarded by many as the best indicator of repeat drug use since it can detect repeat drug use up to a 90-day window.

In fact, it is estimated that over 15% of all hair drug test interpretations will yield inaccurate results - a worrying figure that could have huge implications for your client.

With urine EtG alcohol testing there is about an 80 hour lookback period, with hair follicle EtG alcohol testing detection is up to 90 days. EtG tests are commonly used for individuals on court ordered probation, child custody proceedings and persons in a substance abuse treatment program.

Hair drug testing and bleached hair

Whenever a drug is consumed (smoked, injected, snorted or ingested in any way) the drug metabolises within the body. The drug compounds, metabolites, will be inside the hair as it grows. Bleaching the hair can remove between 40-80% of metabolites found in the hair strand.

The 10 Panel Drug Test (Hair) will identify the presence or absence of ten (10) different classes of commonly abused or misused drugs and/or their metabolites. As a laboratory-based test, this panel includes a routine screen for each drug class, as well as any necessary confirmation testing.

LabCorp offers hair specimen collections in many of our patient service centers (PSCs) located throughout the United States. Our extensive network offers your employees convenient access to a LabCorp PSC.

Hair treatments: Hair treatments, including shampooing, coloring, relaxing, and bleaching the hair, can affect the concentration of drugs and drug metabolites detected during testing. Chemically treated hair may not be appropriate for testing, and untreated hair may need to be taken from another part of the body.

What medications will fail a drug test? ›

Clinically, a false positive urine drug screen can be due to numerous xenobiotics: dextromethorphan, diphenhydramine, doxylamine, ibuprofen, imipramine, ketamine, meperidine, venlafaxine, buproprion, methylenedioxpyrolvalerone (MDPV), and tramadol.

Hair testing is currently not allowed for DOT testing or Federal workplace drug testing. Hair testing is very popular with Non-DOT employers. For head hair the individual will need a minimum of 1.5 inches of hair; otherwise the hair specimen can be body hair.

We offer a robust hair testing menu that screens for a wide range of drugs. Negative hair test results are typically reported within 24 hours of specimen receipt at the laboratory and positive results are confirmed utilizing chromatographic mass spectrometric techniques.

Gas chromatography-mass spectrometry is considered the criterion standard for confirmatory testing. The method is able to detect small quantities of a substance and confirm the presence of a specific drug (eg, morphine in an opiate screen).

The hair drug test can detect drugs effectively for a period of up to 6 months. Longer analysis is possible, but this must be stipulated in a court order. We recommend a maximum of 6 months analysis due to the possible deterioration of older hair.

An often-unacknowledged limitation is that exposure to psychoactive substances is typically not detectable within the first 1–2 weeks post-exposure. Therefore, while hair can allow us to detect exposure to substances within a wide window of time, it typically does not allow us to detect very recent use.

Nails provide up to six months of drug use history and up to three months of alcohol history, according to Lewis. Biomarkers are detectable in nails as early as one week after drug or alcohol use. A typical sample is 2 to 3 millimeters, about the thickness of a quarter.