Nicotine typically leaves your bloodstream within 1 to 3 days after you stop using tobacco products. However, its primary metabolite, cotinine, can remain detectable for a longer period—up to 10 days in blood and saliva, and sometimes even longer in urine and hair follicles

. Here is a detailed breakdown by testing method:

• Blood: Nicotine is usually cleared within 1 to 3 days, while cotinine may be detectable up to 10 days after last use

• Urine: Nicotine and cotinine can be detected for about 3 to 4 days in occasional users, but cotinine can remain for several weeks in regular smokers or those exposed to secondhand smoke

• Saliva: Nicotine can be detected for up to 4 days, with cotinine lasting up to 7 days

• Hair: Nicotine can be detected for up to 90 days or longer depending on hair length and exposure

Nicotine itself has a short half-life of about 2 hours, meaning half of it is eliminated from the body every 2 hours, but cotinine has a longer half-life, making it a more reliable marker for nicotine exposure

. The exact duration nicotine stays in your system depends on factors such as frequency and amount of use, metabolism, age, overall health, and exposure to secondhand smoke

. In summary, while nicotine clears from the blood quickly (within a few days), its byproduct cotinine can be detected for up to 10 days or more, and traces may linger longer in urine and hair tests depending on individual factors. Key points:

• Nicotine clears from blood: 1–3 days
• Cotinine detectable in blood/saliva: up to 10 days
• Nicotine/cotinine in urine: 3–4 days (up to several weeks in heavy users)
• Nicotine in hair: up to 90 days or more
• Half-life of nicotine: ~2 hours

This timeline explains why withdrawal symptoms can start within hours but nicotine metabolites remain detectable for days or weeks after quitting