Learn · Nicotine
How long does nicotine stay in your system?
Nicotine itself leaves your blood within about 1 to 3 days of your last cigarette or vape. What lingers is cotinine, the substance your body breaks nicotine down into, and it is what most tests actually look for. Cotinine is typically detectable in urine for around 3 to 4 days, longer in heavy users, and in hair for months.
Nicotine vs cotinine
This is the detail that trips people up. Nicotine has a short half-life, roughly 1 to 2 hours, so it drops out of your blood fast. Your liver turns it into cotinine, which hangs around much longer, with a half-life of about 16 to 20 hours. Because cotinine is more stable and lasts longer, it is the marker nicotine tests measure rather than nicotine itself.
Detection windows by test type
| Test | Typically detectable for |
|---|---|
| Blood | Nicotine 1 to 3 days; cotinine a few days longer |
| Saliva | Around 1 to 4 days (cotinine) |
| Urine | Around 3 to 4 days for regular users, longer for heavy use |
| Hair | Up to several months |
These are general ranges. How long it takes to clear depends on how much and how often you used nicotine, your metabolism, age, and other factors, so individual results vary.
What this means if you're quitting
The fast clearance of nicotine is why the physical withdrawal is front-loaded: the drug is gone within a few days, which is exactly when cravings peak, around 72 hours, before your brain adjusts. The tests detect cotinine for longer, but your body has done the hard part of clearing the nicotine well before that.
Clear the nicotine, keep it out
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Launching August 15, 2026Common questions
How long does nicotine stay in your system?
Nicotine itself leaves your blood within about 1 to 3 days of your last cigarette or vape. But tests usually look for cotinine, the substance your body breaks nicotine into, which lasts longer: it is typically detectable in urine for around 3 to 4 days, and longer in heavy users. Hair tests can detect it for months.
How long does nicotine show up in a urine test?
A urine test looks for cotinine, which is usually detectable for about 3 to 4 days after your last nicotine use in a regular user, and sometimes longer. Occasional or light users may clear it faster.
How long does nicotine stay in your blood?
Nicotine has a short half-life of around 1 to 2 hours, so it drops quickly and is mostly gone from your blood within 1 to 3 days. Cotinine, its longer-lasting breakdown product, can be detected in blood for a few days longer.
Related: nicotine half-life · withdrawal symptoms. Sources: NHS. General information, not medical advice.