What Drugs Show in a Hair Follicle Test? Every Panel, Drug Class and Prescription Explained

Updated 19 Oct 2026 · By the DrugTestAnswers Editorial Team

A standard hair follicle test looks for five drug groups: marijuana, cocaine, amphetamines (which includes meth and ecstasy), opiates such as heroin, morphine and codeine, and PCP. Bigger panels add prescription opioids like oxycodone and hydrocodone, benzodiazepines, barbiturates, methadone and, more and more often, fentanyl. Alcohol can be tested in hair too, but only when the employer orders a separate EtG test. Which drugs show up on yours depends entirely on the panel your employer or lab picked, so the list below walks through each one, what the lab actually measures, and the things hair tests usually don't catch. We may earn a commission if you buy through our links.

The quick list

If you only need the short version, here is what each common hair panel covers. Labs name their panels a little differently, so treat this as a guide and ask the collection site for the exact list on your order.

For a side-by-side look at the two most common choices, see our guide to the 5-panel vs 10-panel hair follicle test.

How a drug ends up in your hair at all

When you use a drug, it and the chemicals your body breaks it into travel through your blood. The tiny blood vessels that feed each hair follicle pass some of that material into the growing hair shaft, where it gets locked into the protein as the hair forms. Sweat and the oil glands on your scalp add a little more from the outside. As the hair keeps growing, that section moves up and away from the scalp, which is why a lab can read roughly the last three months from the 1.5 inches closest to your head.

Two practical points follow from this. First, very recent use usually isn't visible yet, because hair that formed in the last week or so is still below the skin. Second, the lab is measuring a drug that's part of the hair itself, not sitting on it, so the question "what drugs show" is really "what drugs and breakdown products does this lab's panel screen for, at what cutoff".

Marijuana (THC)

Every standard hair panel includes marijuana, but it's the trickiest one for labs. The main active ingredient, THC, doesn't move into hair very well, so the amounts found are tiny. To make sure a positive comes from actual use and not smoke in the room, good labs confirm with THC-COOH, a breakdown product your body makes only after the drug has been in your system. Because the amounts are so small, marijuana cutoffs are set in fractions of a picogram per milligram of hair, far lower than for any other drug on the panel.

What that means in practice: regular and daily users are very likely to show up, while a single use or very occasional use often falls below the cutoff. It isn't a safe bet either way. Edibles, vapes and smoked flower all produce THC-COOH, so the form you use doesn't change which drug the test is looking for. Delta-8 THC products also break down into a THC-COOH that standard tests can't reliably tell apart from the regular kind. Full-spectrum CBD products may contain small amounts of THC.

Cocaine

Cocaine shows up in hair more strongly than almost anything else. The lab confirms cocaine itself plus breakdown products such as benzoylecgonine and norcocaine, and when someone drinks while using it, a compound called cocaethylene. Looking at these breakdown products lets a lab separate actual use from cocaine dust that landed on the hair. A screening cutoff of around 500 picograms per milligram is common in workplace hair testing, though each lab sets its own. Crack and powder cocaine look the same to the test.

Cocaine also binds more tightly to darker hair, which is one reason researchers have raised fairness questions about hair testing. Our page on hair follicle tests after cocaine covers detection time and contamination in more depth.

Amphetamines, meth and ecstasy

The amphetamines group covers amphetamine, methamphetamine, MDMA (ecstasy or molly) and the closely related MDA. These drugs enter hair readily, so regular use is usually easy for a lab to see. Prescription stimulants for ADHD matter here. Adderall is mixed amphetamine salts, so it will show up as amphetamine, and Vyvanse turns into amphetamine in the body as well. A valid prescription doesn't stop the drug from appearing on the lab report; it's handled at the review step described below.

Methylphenidate (Ritalin, Concerta) is a different chemical and isn't part of the standard amphetamine screen. It only appears if a lab adds it on purpose.

Opiates and prescription opioids

The basic opiate screen targets codeine and morphine, plus 6-acetylmorphine (6-AM), a marker that only comes from heroin. Finding 6-AM in hair is strong evidence of heroin use specifically, since morphine and codeine could also come from prescriptions or, in very small amounts, from poppy seeds. Poppy seeds are far less of a concern in hair than in urine because eating them puts only a tiny amount into the bloodstream.

Semi-synthetic painkillers such as oxycodone (OxyContin, Percocet), hydrocodone (Vicodin, Norco), oxymorphone and hydromorphone (Dilaudid) are not reliably picked up by a basic opiate screen. That's why many employers now order an "expanded opiates" panel that lists them by name. If you're prescribed one of these, assume it will show up if your panel includes expanded opiates.

PCP

Phencyclidine is still on the standard five-drug list largely for historical reasons. It's rarely used today, and positives are uncommon, but it remains on most basic hair panels because it was part of the original federal list of five.

What larger panels add

Benzodiazepines

Drugs such as alprazolam (Xanax), diazepam (Valium), clonazepam (Klonopin) and lorazepam (Ativan) appear on 7-panel tests and up. These are harder to measure in hair because the doses are small, so labs list the specific benzos they test for. A lab that screens for one benzo may not catch another.

Barbiturates

Butalbital (found in some headache medicines) and phenobarbital are the barbiturates people are most likely to encounter. They show up on 10-panel tests and above.

Methadone and buprenorphine

Methadone has been on expanded panels for years. Buprenorphine (Suboxone, Subutex) is increasingly added, especially by treatment programs that want to confirm someone is taking a prescribed medication.

Fentanyl

Because of the overdose crisis, a growing number of employers add fentanyl to hair panels, and some labs now offer it as a standard add-on. A basic opiate screen will not catch fentanyl; it has to be ordered by name.

Tramadol, meperidine and ketamine

These are typically found on 12-panel to 17-panel tests. Tramadol in particular shows up on more panels now that it's widely prescribed.

Alcohol in a hair test

Hair can show alcohol use, but only through a separate test. The lab looks for ethyl glucuronide (EtG), a breakdown product your body makes from alcohol, or for fatty acid ethyl esters. The Society of Hair Testing has suggested that EtG at or above about 5 pg/mg points to repeated drinking, and at or above about 30 pg/mg points to chronic heavy drinking. A single drink or an occasional glass of wine generally won't register. Hair-care products that contain alcohol can affect the results, and frequent bleaching or perms can lower EtG levels. Most job hair tests don't include alcohol at all unless the employer orders it specifically.

What hair tests usually miss

• Very recent use: roughly the last 7 to 10 days, since that hair hasn't grown out yet.
• Synthetic cannabinoids ("spice", "K2"): only found with a special panel; the chemicals change too often for standard screens.
• Kratom: not on routine panels; a few labs offer it separately.
• Psilocybin and LSD: rarely tested in hair. LSD is active at such small doses that it's very hard to measure in hair.
• Inhalants and nitrous oxide: not detected.
• Nicotine: not on drug panels, though some life-insurance labs test hair for cotinine separately.
• Steroids: possible in specialist labs but not part of workplace panels.

"Not on the panel" doesn't mean "can't be found". If a lab is asked to look for something specific, hair often holds it.

Cutoff levels, in plain words

A drug only counts as positive if the amount in your sample is above the lab's cutoff. Cutoffs are given in picograms of drug per milligram of hair (pg/mg). To put the unit in perspective, a picogram is one trillionth of a gram. Some rough patterns:

• Marijuana cutoffs are tiny because THC moves into hair so poorly; confirmation is often below 1 pg/mg.
• Cocaine and amphetamines have much higher cutoffs, commonly in the hundreds of pg/mg, because they bind to hair so well.
• Opiates usually sit in between, with around 200 pg/mg a commonly cited screening level for codeine and morphine.

Each lab publishes its own numbers, and federal agencies have proposed cutoffs for hair testing, so ask for the lab's list if your result matters. If you have a report in hand, the lab or the medical review officer can explain which cutoff applied to each drug on it.

Screening and confirmation: the two steps

Every hair sample goes through two stages. The first is a fast screening test (usually an immunoassay) that flags samples that might contain a drug class. Anything that's flagged then goes to a second, much more precise test, usually liquid or gas chromatography with mass spectrometry, which identifies the exact drug and measures how much is there. A sample is only reported positive if it passes the confirmation cutoff. This is why hair tests rarely produce false positives from foods or over-the-counter medicines; the confirmation step names the specific molecule.

Labs also wash the hair before testing to remove anything sitting on the surface, then check the wash liquid to see whether outside contamination is likely. Breakdown products that only your body can make are the strongest proof of use.

Prescriptions: what happens if yours shows up

A prescription doesn't make a drug invisible on a hair test. In a properly run workplace program, a positive result goes to a medical review officer (MRO), a doctor who contacts you before your employer sees anything. You can then show your prescription. If it explains the result, the MRO reports the test as negative to the employer. Have your pharmacy records or prescription bottle handy and answer the MRO's call; missing it can lead to the result being reported as positive.

A few things the MRO step won't cover: marijuana is still treated as a positive by many employers even in states with medical or recreational laws, and someone else's prescription doesn't count as yours.

Does hair color or type change what shows?

It can change how much shows. Melanin, the pigment that makes hair dark, holds onto cocaine, amphetamines and some opioids more tightly, so darker hair may test higher for the same use. Marijuana is less affected. Bleaching, dyeing and perming can lower drug levels somewhat, but they also damage the hair in ways a lab may notice, and they don't reliably remove what's inside. Our page on hair dye and hair follicle tests covers what studies have found.

Head hair vs body hair

If you have little or no head hair, the collector usually takes hair from your arms, legs, chest or underarms. The same panel of drugs is tested, but body hair grows more slowly and in cycles, so it can reflect a longer period, sometimes up to a year. Body hair results can look different from head hair results for the same person, and some labs flag them accordingly.

How far back each drug shows up

For a standard sample of 1.5 inches of head hair, every drug on the panel has roughly the same window: about the last 90 days, minus the most recent week or so. That's different from urine, where marijuana can linger for weeks while cocaine clears in a few days. Hair doesn't care how quickly your body processes a drug; it only records what was in your blood while that hair was forming. Our page on how long it takes to pass a hair follicle test runs through the timing math month by month.

Check what your own hair shows

If you're worried about a test coming up, the most useful thing you can do is find out what your hair would actually show before anyone else sees it. A mail-in home kit like Hair Confirm uses lab analysis similar to an employer test, covers the main drug groups, and keeps the result private. Our list of the best hair follicle drug test kits compares panels and turnaround times so you can match the kit to the panel you expect.

Product facts: Old Style Aloe Toxin Rid

People who learn which drugs show up in hair often go on to look at cleansing shampoos. The one most often named is Old Style Aloe Toxin Rid from TestClear. Here's what's known:

• What TestClear says: it's a deep-cleansing shampoo meant to remove residue and buildup from hair and scalp.
• Maker's directions, briefly: wash with a regular shampoo first, work Aloe Toxin Rid into damp hair and scalp, leave it for 10 to 15 minutes, rinse, and repeat across several days before the test.
• What isn't proven: no independent published research shows it gets anyone past a hair drug test, and nothing guarantees a result. It doesn't change which drugs a lab screens for, and not using is the only certain way to pass.
• Macujo and Jerry G: some people combine it with these multi-step routines, which add vinegar, salicylic acid products or bleach and dye. They're harsh on the scalp, unproven, and should never involve mixing bleach with acids or household cleaners.

You can check current pricing for Old Style Aloe Toxin Rid at TestClear. Our Aloe Toxin Rid review and how-to guide covers directions and the evidence gaps in full.

Questions worth asking before your test

1. Which panel did the employer order? The collection site or HR can tell you the panel number and whether it includes expanded opiates or fentanyl.
2. Is it head hair or body hair? This changes how far back the test reaches.
3. Is alcohol (EtG) included? It usually isn't, but it's worth knowing.
4. Who reviews positives? Make sure there's a medical review officer step if you take prescription medicines.

Where these facts come from

Drug lists reflect typical panels offered by major US workplace testing labs. Cutoff patterns are drawn from published lab guidance, the Society of Hair Testing consensus on alcohol markers, and federal proposals for hair testing. See our editorial methodology for how we check sources.

Tests this guide does not cover

None of this is meant for DOT-regulated tests, FAA aviation tests, federal employee programs, military testing, or court, probation and parole testing. Don't use any product mentioned here to try to influence those tests; tampering may be illegal and can be treated as a refusal.

Disclaimer and where to get help

This page is for information only and isn't medical or legal advice. Trying to tamper with a drug test may be illegal and can count as a refusal or a failure. Not using is the only guaranteed way to pass. If you'd like to talk to someone about substance use, the SAMHSA National Helpline is free, confidential and open around the clock at 1-800-662-4357. In a crisis, call or text 988.