how long will nicotine show up on a blood test?
Stop for 2 weeks: To be safe, you might want to stop smoking for a couple weeks. They are testing for cotinine which is a metabolite of nicotine. It has a long half life up to 40 hours. This tests shows positive for both active smokers and those who have quit but are using nicotine patch, gum, etc. Another test is used to identify active smokers. It is called anabasine and found in tobacco products.