UK drug detection times
How long common drugs stay detectable in urine, blood, saliva and hair — for UK workplace, court, driving and family-court testing.
| Drug | Urine | Blood | Saliva | Hair |
|---|---|---|---|---|
Alcohol ethanol | 12–48 hours (EtG up to 80 hours) | Up to 12 hours | Up to 12 hours | Up to 90 days (EtG hair test) |
Cannabis (THC) weed, hash, edibles | Occasional: 3–7 days. Daily: 30–60 days | 1–2 days (chronic: up to 7) | 24–72 hours | Up to 90 days |
Cocaine coke, charlie | 2–4 days (chronic: up to 10) | Up to 12 hours | 1–2 days | Up to 90 days |
Crack cocaine | 2–4 days | Up to 12 hours | 1–2 days | Up to 90 days |
Ketamine K, ket | 2–4 days | Up to 24 hours | 1–2 days | Up to 90 days |
MDMA ecstasy, mandy, molly | 1–3 days | 1–2 days | 1–2 days | Up to 90 days |
Heroin diamorphine, gear | 1–3 days | Up to 12 hours | 1–2 days | Up to 90 days |
Methadone | 3–4 days | 1–2 days | 1–2 days | Up to 90 days |
Codeine | 1–2 days | Up to 24 hours | 1–2 days | Up to 90 days |
Tramadol | 1–4 days | Up to 24 hours | 1–2 days | Up to 90 days |
Oxycodone | 1–3 days | Up to 24 hours | 1–2 days | Up to 90 days |
Diazepam (Valium) blues, benzos | Up to 10 days (chronic: 4–6 weeks) | 6–48 hours | 1–10 days | Up to 90 days |
Xanax (alprazolam) bars | 4–5 days | Up to 24 hours | 1–2 days | Up to 90 days |
Pregabalin (Lyrica) bud, pregabs Not on standard NHS or workplace panels — needs a specific test. | 5–7 days | Up to 36 hours | 1–2 days | Up to 90 days |
Zopiclone z-drug, zimmos | Up to 48 hours | Up to 24 hours | 1–2 days | Up to 90 days |
Amphetamine speed | 1–3 days | Up to 12 hours | 1–2 days | Up to 90 days |
Methamphetamine crystal meth, tina | 3–6 days | 1–3 days | 1–4 days | Up to 90 days |
GHB / GBL | Up to 12 hours | Up to 8 hours | Up to 6 hours | Up to 30 days |
Nitrous oxide balloons, nos Nitrous is not on any standard drug panel. | Not routinely detected | Minutes only | Not detected | Not detected |
LSD | 1–3 days | Up to 12 hours | Up to 3 days | Up to 90 days |
Ecstasy tablets | 1–3 days | 1–2 days | 1–2 days | Up to 90 days |
Buprenorphine (Subutex) | 2–4 days | Up to 36 hours | 1–3 days | Up to 90 days |
Common questions
How reliable are these times?▾
These windows are typical ranges for a person of average weight and metabolism. Body fat, hydration, dose, frequency of use, and the sensitivity of the test all shift the actual number. Chronic daily use extends every window listed.
What does a UK workplace drug test cover?▾
Most UK workplace panels are 5-panel or 10-panel urine tests: cannabis, cocaine, opiates, amphetamines and benzodiazepines are almost always included. Pregabalin, gabapentin, zopiclone, nitrous oxide and most 'legal high' compounds are usually not on the standard panel.
Does drinking water flush drugs out?▾
Not meaningfully. Excessive water can dilute a urine sample enough that a lab flags it as invalid, which usually triggers a re-test. Nothing shortens the detection window materially except time.
What is a hair test?▾
Hair testing looks at the outer 3cm of head hair, which grows about 1cm per month — giving a rolling 90-day picture. It is used by family courts (CAFCASS), some employers, and by rehab providers who want to verify long-term abstinence.
Related
These are typical windows, not guarantees. Any individual result depends on dose, frequency, body composition and the specific test used.