Most people asking how long cannabis stays in your hair follicles are surprised by the answer: a standard hair test can typically detect THC metabolites for about 90 days, and daily, heavy consumers sometimes register a bit longer. Unlike blood, urine, or saliva, hair traps cannabinoid byproducts as it grows, which gives it the longest detection window of any common screen. The exact number depends on your body, your use pattern, and the test itself.
How long does cannabis stay in your hair follicles?
Roughly 90 days is the standard answer. Head hair grows about half an inch per month, and a lab sample usually takes the closest 1.5 inches to the scalp, which reflects about a three-month history. Occasional users may clear in 30 to 60 days, while very frequent consumers of high-potency products can still test positive past 90 days. Body hair grows more slowly and can hold metabolites even longer.
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Key Features That Shape Your Detection Window
- Frequency of use: daily or multiple-times-a-day use leaves more metabolite embedded in the shaft than a single session.
- Potency and method: concentrates, dabs, and edibles can deliver a heavier cannabinoid load than a low-THC flower joint.
- Your metabolism: body fat percentage, hydration, activity level, and general health all influence how quickly byproducts clear.
- Sample site and length: a 1.5-inch scalp sample covers the last three months or so, while body hair covers a longer window.
- Product type: full-spectrum products may carry trace THC, while isolate-based products typically carry less.
- Test sensitivity: lab cutoffs vary, and a more sensitive panel can flag lower concentrations.
- Individual biology: age, genetics, and medications can shift timelines slightly from person to person.
How Hair Testing Actually Works
A technician cuts a small, pencil-thin sample close to the scalp, then the laboratory washes it and screens it, usually with an immunoassay followed by gas or liquid chromatography mass spectrometry for confirmation. Results are reported in picograms per milligram of hair, and most confirmatory cutoffs sit at a low threshold, which is why even modest exposure can be picked up. Bleaching, dyeing, or treating hair may reduce detected levels in some cases, but it does not reliably produce a negative result and can damage the sample.
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Can you flush THC out of your hair before a test?
Not reliably. Once metabolites are woven into the keratin structure, no shampoo, detox drink, or home remedy removes them with any consistency, and most commercial claims are not supported by lab evidence. The only dependable approach is time.
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Is a hair test more accurate than a urine test?
Hair testing offers a longer look-back window and is harder to tamper with, but it cannot show how recently or how often someone used. Urine, by contrast, is better at catching recent use within a few days.
Ordering From Eden Cannabis
Every order placed with Eden Cannabis ships in plain, discreet packaging with no cannabis branding on the exterior, and tracking is provided as soon as your parcel leaves our facility. We follow all state packaging and labeling requirements, offer in-store pickup at our retail location, and accept returns on unopened, factory-sealed accessories within our standard window. If anything arrives damaged or incorrect, contact our support team and we will make it right.