Thursday, April 17, 2014
Smoking and Tobacco
Nicotine Levels in Blood
How long does nicotine stay in your system and show on a blood test after you smoked your last cigarette?
According to Dr. Mary Ellen Wewers, Professor & Associate Dean for Research, Interim Director, Center for Health Outcomes, Policy and Evaluation Studies (HOPES), The Ohio State University School of Public Health:
"Nicotine has a short half-life (2-4 hours) so often it is not detectable after 24 hours. Cotinine, its major metabolite, has a half-life of 16-19 hours so it usually is detectable for 4-7 days, depending upon amount of consumption."
It's hard to answer your question; it definitely depends on the amount of nicotine in the tobacco product, how much is used, and how it is used. Cotinine can be detected in the saliva as well. Other sources for information on Cotinine are:
(See the CDC's Third National Report on Human Exposure to Environmental Chemicals: "Spotlight on Cotinine," July 2005)
Kathy Vesha, RN, BSN, MA
The Ohio State University