To detect the presence of and/or measure the quantity of nicotine or cotinine in blood, urine, saliva, or sometimes hair; to determine whether someone uses tobacco or has been exposed to secondhand smoke; sometimes performed to evaluate for acute nicotine poisoning
Nicotine / Cotinine
Whenever someone requires confirmation of tobacco usage or exposure to secondhand smoke; occasionally when nicotine overdose is suspected
Nicotine is an addictive chemical found in the tobacco plant and concentrated in its leaves. It is inhaled with each puff on a cigarette and ingested with chewing tobacco and subsequently absorbed into the blood. This testing detects and/or measures nicotine and its primary breakdown product (metabolite) cotinine in the blood, urine, saliva, or hair.
Nicotine is metabolized by the liver into more than 20 compounds, which are eliminated from the body in the urine. Both tobacco use and exposure to tobacco smoke can increase nicotine and cotinine concentrations in the body. Levels also rise with use of nicotine replacement products such as nicotine patches and gums. In large amounts, nicotine can be poisonous.
Cotinine is usually the test of choice to evaluate tobacco use or exposure to tobacco smoke because it is stable and is only produced when nicotine is metabolized. Cotinine has a half-life in the body of between 7 and 40 hours, while nicotine has a half-life of 1 to 4 hours.
Blood and/or urine cotinine tests may be ordered along with nicotine tests. In some cases, other nicotine metabolites, such as nicotine-1'-N-oxide, trans-3'-hydroxycotinine, or nornicotine, or other tobacco chemicals, such as anabasine in urine, may also be tested. The presence of anabasine in someone's urine indicates that the person is actively using a tobacco product, as it is not found in commercial nicotine replacement products, such as a patch.
The presence of nicotine and/or cotinine in an individual's sample may indicate the use of tobacco products or exposure to environmental tobacco smoke. Testing may be used in a number of situations to evaluate the possible use of tobacco products, such as in smoking cessation programs, prospective employment assessments, and evaluations of applicants for health or life insurance.
Nicotine and cotinine testing may also be ordered in cases of suspected nicotine poisoning. Acute overdoses of nicotine, such as might happen if a child ingests nicotine lozenges or gum, are relatively rare but generally require immediate medical attention. Symptoms can include a burning mouth, nausea, abdominal pain, salivating (drooling), diarrhea, sweating, confusion, dizziness, agitation, increased heart rate, rapid or difficult breathing, convulsions, coma, and even death.
How is the sample collected for testing?
A blood sample is obtained by inserting a needle into a vein in the arm and/or a random urine sample is collected. Occasionally, a saliva sample may be obtained, directly or by soaking a collecting cloth or swab with saliva. Rarely, a hair sample may be collected.
Is any test preparation needed to ensure the quality of the sample?
No test preparation is needed.
How is it used?
Nicotine, or its primary metabolite cotinine, is most often tested to evaluate tobacco use. Long-term smoking of tobacco products can increase the risk of developing many diseases including lung cancer, COPD, stroke, heart disease, and respiratory infections. Long-term tobacco use can also exacerbate asthma and help promote blood clot formation. In pregnant women, smoking can impair growth of the developing baby and lead to low birth weight babies.
Because use of tobacco products can greatly affect the health of individuals, companies may use nicotine/cotinine testing to evaluate prospective employees for tobacco use. Many health and life insurance companies test applicants for nicotine or cotinine as well.
Nicotine and cotinine can both be measured qualitatively or quantitatively. Qualitative testing detects the presence or absence of the substances, while quantitative testing measures the concentration of the substance. Quantitative testing can help distinguish between active smokers, tobacco users who have recently quit, non-tobacco users who have been exposed to significant environmental tobacco smoke, and non-users who have not been exposed.
Cotinine may also be measured in saliva and in hair, although hair testing is primarily used in a research setting, such as a study of non-smokers exposure to tobacco smoke.
A blood or urine nicotine test may be ordered by itself or along with cotinine if a health practitioner suspects that someone is experiencing a nicotine overdose.
When a person has reported that he or she is using nicotine replacement products but is no longer smoking, nicotine, cotinine, and urine anabasine measurements may sometimes be ordered. Anabasine, an alkaloid, is present in tobacco but not in commercial nicotine replacement products. If a sample tests positive for anabasine, then the person is still using tobacco products.
When is it ordered?
Cotinine and/or nicotine testing may be ordered whenever an evaluation of tobacco use status or tobacco smoke exposure is required.
A court may order testing for child custody purposes. When a person enters a smoking cessation program, blood or urine cotinine tests may be ordered to evaluate his or her compliance. Urine, blood, or saliva testing may serve as a screen for tobacco use when someone is applying for life or health insurance. Since smoking can increase the risks of medical complications, testing may be performed prior to orthopedic, spinal fusion, wound revision, and plastic surgery as well as pulmonary therapy and organ transplantation.
Nicotine and cotinine are sometimes measured when someone has symptoms that a health practitioner suspects may be due to a nicotine overdose. Symptoms of mild nicotine poisoning may include:
- Nausea, vomiting
More serious nicotine poisoning may result in:
- Increased blood pressure and/or heart rate, which suddenly drops
- Slowed or difficulty breathing
- Abdominal cramps
- Agitation, restlessness, or excitement
- Burning sensation in mouth
- Muscular twitching
- Seizures, convulsions
Hair testing is rarely performed in a clinical setting but may be ordered when an evaluation of longer-term tobacco use is desired.
What does the test result mean?
In the blood, the nicotine level can rise within a few seconds of a puff on a cigarette. How much it rises depends on the amount of nicotine in the cigarette and the manner in which a person smokes, such as how deeply he or she inhales. The rate at which nicotine is metabolized and cotinine is cleared from the body also varies from person to person due to some genetic differences.
When someone stops using tobacco and nicotine products, it can take more than two weeks for the blood level of cotinine to drop to the level that a non-tobacco user would have and several weeks more for the urine level to decrease to a very low concentration.
In general, a high level of nicotine or cotinine indicates active tobacco or nicotine replacement use. A moderate concentration indicates a tobacco user who has not had tobacco or nicotine for two to three weeks. A lower level may be found in a non-tobacco user who has been exposed to environmental smoke. Very low to non-detectible concentrations are found in non-tobacco users who have not been exposed to environmental smoke or in tobacco users who have refrained from tobacco and nicotine for several weeks.
When a nicotine overdose is self-evident, the person may not be tested for nicotine or cotinine. The concentration would typically be increased, but the level does not necessarily correlate with the severity of a person's symptoms.
Is there anything else I should know?
Test results based on different samples (blood, urine, saliva) are not interchangeable.
Some pesticides contain high concentrations of nicotine. This can be another source of nicotine poisoning. In fact, nicotine is itself a pesticide sometimes used in "organic" farming as an alternative to organophosphate or pyrethrinoid derivatives.
Nicotine is found not just in the tobacco plant but also in other plants in the same family. These include potatoes, tomatoes, eggplants, and red peppers. The concentration of nicotine in these plants, however, is much lower than that in tobacco. The cutoffs of the nicotine/cotinine tests have been set to discriminate dietary sources of nicotine from tobacco use and second-hand smoking.
A person's genetic makeup may influence how they metabolize nicotine. Variations in the genes that code for the CYP2A6 and CYP2B6 liver enzymes affect the rate of nicotine metabolism. (For more on this, see our article on Pharmacogenetic Tests.)
Do any forms of tobacco not contain nicotine?
No, they all contain nicotine. This includes pipe tobacco, cigars, snuff, chewing tobacco, etc. If you use any of these, nicotine may be detected in your system.
Can I be required to take a test for tobacco use?
Since tobacco use is legal for adults, any testing requirement would generally only apply to people who are court-ordered to be tested, such as for child custody reasons. However, since smokers tend to have higher health costs and are at an increased risk for developing a variety of diseases, some health and life insurance companies may require their applicants to be tested for tobacco use prior to accepting them as clients.
Where can I find information about quitting smoking?
What kinds of nicotine replacement products are available?
There are a variety of over-the-counter (OTC) products and a few that are available by prescription. OTC products include nicotine gum, patches, and lozenges. Some companies market e-cigarettes as smoking cessation aids, but the Food and Drug Administration has not approved them for this purpose, and some research has found that many elements in e-cigarette vapor can cause respiratory distress and disease. Nicotine products available by prescription include patches, inhalers, and nasal sprays. It is important to follow directions for their use and to keep them away from children. The products should be used in conjunction with a smoking cessation program. Talk to your health care provider about the best options for you. For more information, see the MedlinePlus page on Nicotine replacement therapy.
On This Site
Elsewhere On The Web
American Cancer Society: Questions About Smoking, Tobacco, and Health
National Cancer Institute: Harms of Smoking and Health Benefits of Quitting
Centers for Disease Control and Prevention: Smoking & Tobacco Use
CDC Vital Signs: Tobacco Use – Smoking
American Lung Association: Getting Help to Quit Smoking