Ash asked
How long does nicotine stay in your system?
Answer
The amount of time that nicotine, and the byproducts of nicotine metabolism (cotinine and nicotine-1'-oxide), stay in your system depends on a person’s genetics, circumstance (e.g age, kidney, and liver function) and the mode and frequency of exposure.
For most individuals:
- Nicotine is present in the bloodstream for one to three days, with times greatly increasing in chronic nicotine users.
- Cotinine, a by-product of nicotine metabolism, lasts much longer, up to 10 days and sometimes longer in chronic nicotine users.
- Nicotine is stored in small amounts in hair follicles. If testing hair for nicotine, it may be present for 3-12 months
Below, we discuss nicotine and how long is lasts in the body in more detail.
How Long Nicotine Stays In The Body
When smoking nicotine containing products, nicotine reaches the brain in as little as 7 seconds. When trying to determine how long it lasts in the body, you must account for both nicotine, and metabolism by-products, cotinine and nicotine-1'-oxide.
Whether the source of exposure is from one of the nicotine replacement products or from smoking or chewing tobacco, nicotine is absorbed into the bloodstream. Once the nicotine is absorbed into the bloodstream, an enzyme in the liver breaks it down to cotinine and nicotine-1'-oxide.
The half-life (i.e. time it takes for 50% of a drug to be metabolized) of nicotine and by-products are extremely variable, with the half-life greatly increasing in chronic nicotine users (e.g. chronic smokers).
In non-frequent users, the half-life of nicotine is reported to be very short, only 1 to 2 hours. However, nicotine can build up in the system of frequent users take longer to metabolize.
While one nicotine metabolite, nicotine-1'-oxide, has a short life, the other by-product of metabolism, cotinine, has a half-life of 10-40 hours!
Both unchanged (i.e. non-metabolized) nicotine and the metabolism by-products (e.g. cotinine) are excreted in the urine. Based on the half-life data:
- Nicotine is generally detectable in the urine for around 1 day in acute users and up to 3 days for chronic users.
- Cotinine is generally detectable in the urine for up to 10 days.
If testing for nicotine from other sources than urine, it can be detected for considerably longer periods of time. Aside from urine, both nicotine and cotinine can be detected in the:
- Blood
- Saliva
- Hair
While saliva and blood have similar, if not slightly longer, detection times in the body when compared to urine, nicotine is found in trace amounts in the hair follicles. If hair is used in testing for nicotine, it can be detectable for 3 to 12 months!
Summary
- Nicotine has a half-life of one to two hours and is generally detectable in the urine for one to three days, depending on frequency of nicotine use.
- The nicotine metabolism by-product cotinine, has a significantly longer half-life of 10 to 40 hours. It is generally detectable in the urine for up to 10 days.
- Nicotine can be detected in the hair for 3 to 12 months.
