Cotinine is a metabolite (byproduct) of nicotine as it is “processed” by the human body. It is an indicator that nicotine has been inhaled or otherwise introduced into the body.
Cotinine is a chemical that is made by the body from nicotine, which is found in cigarette smoke. Since cotinine can be made only from nicotine, and since nicotine enters the body with cigarette smoke, cotinine measurements can show how much cigarette smoke enters your body.
As far as we know, cotinine itself is not harmful. Cotinine is used simply to measure how much tobacco smoke has entered your body. However, many studies show that some of the 4,000 other chemicals found in tobacco smoke are harmful
The only way to reduce your cotinine level is to stop or reduce your exposure to cigarette smoke.
Depending on how high your level is to begin with, your level could drop to that of a nonsmoker in 7 to 10 days.
Cotinine has an in vivo half life of about 24 hours. Nicotine’s half-life is about 30 minutes. Timing of sampling relative to the last cigarette smoked may account for some fluctuation of cotinine levels in steady smokers. For smokers with a fairly constant smoking pattern, cotinine levels reach a steady state, varying only by 15%-20% over the course of the day. Levels should be lowest in the morning as there is typically minimal exposure to cigarette smoke overnight. Once a sample is collected, metabolism ceases and cotinine levels should not change; however, saliva or urine left at room temperature for extended periods may experience degradation of cotinine due to bacterial contamination.
The methods for flushing out Cotinine are much the same as Nicotine, which we discussed in How Long Does Nicotine Remain In Your Body? Hours? Days?.