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A. Schuyler, NP
A. Schuyler, NP, Nurse Practitioner
Category: Health
Satisfied Customers: 15936
Experience:  Board Certified NP, MS, RN. 25 years private practice & hospitalist
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what cotinine levels are considered to be a non smoker? and

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what cotinine levels are considered to be a non smoker? and how long if you quit smoking do your levels get to that levels necessary? in other words how quickly to your levels drop the moment you stop smoking to as a non smoker that would tell the doctor you are nicotine and cotinine level free... and does it make a difference how many cigaretts you smoke a day? after you have quit? ex: if u smoked 15 then dropped to 5 then 2 then 1 are ur levels dropping the less u smoke, especially if you have been drinking a lot of water?


Answers provided are for informational use only and do not confer patient-provider relationship. Please let me introduce myself. My name is XXXXX XXXXX I will do whatever I can to help you.


Cotinine is a metabolite of nicotine and is used to measure one's exposure to tobacco products. It is most commonly tested for in urine and blood, and most often in urine since that test in non-invasive.


A non-smoker has levels of less than 1 ng/mL. In blood a level less than 10 ng/mL and in urine <11 ng/mL is considered non-smoking. It takes about 2 weeks after the last smoke for cotinine levels to fall to near normal levels in a blood test. Since cotinine remains in urine much longer, it can take several weeks for it to be normal after completely stopping.


How many cigarettes one smokes does matter, since the higher the number the higher the cotinine levels will be. Only with no smoking at all will one accomplish the levels of a non-smoker and it will take a minimum of 2 weeks for a blood test and 4-6 weeks of complete non-smoking for a urine test.


Not only how many cigarettes, but also the type of cigarette (high versus low nicotine, menthol versus non-menthol), how deeply one inhales, and even their genetic make-up contribute to the overall time it takes to reach non-smoking levels.


Please let me know if you have questions.


Best regards,





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