Nicotine and Cotinine

Nicotine and cotinine testing detect evidence of nicotine use and presumed tobacco usage. Testing is most often performed on a sample of urine or saliva, but may also be performed on samples of blood or hair. Nicotine and cotinine testing may be used in a variety of circumstances, including prior to starting a new insurance policy and to confirm that a person has quit using tobacco in a smoking cessation program.

Purpose of the test

A nicotine or cotinine test is used to detect evidence of nicotine use and presumed tobacco usage. Testing may be performed in a variety of settings:

• Smoking cessation programs: Levels of nicotine and/or cotinine may be measured to estimate the amount of nicotine consumed before quitting, as well as to confirm that a person has quit using tobacco and other nicotine products.
• Insurance medical exam: While not all insurance companies require a medical exam or nicotine and cotinine testing, some may require that applicants be tested for nicotine exposure as part of a medical exam performed prior to approving an insurance policy.
• Employment testing: Many employers restrict tobacco use in the workplace, and nicotine or cotinine tests may be required when a person applies at a job that prohibits smoking.
• Medical testing: Nicotine exposure may be measured prior to qualifying for a surgery or organ transplantation, as well as in cases of suspected nicotine poisoning. Tobacco use increases the risk of poor wound healing and can cause additional side effects after an organ transplant. Although nicotine poisoning is uncommon, it most often occurs in children who accidentally ingest nicotine patches, nicotine gum, or e-cigarette liquid.

What does the test measure?

Nicotine is an addictive chemical naturally found in the leaves of tobacco plants. After being fermented and dried, tobacco leaves may be smoked, chewed, or sniffed. Nicotine can also be produced synthetically in a laboratory, called freebase nicotine or nicotine salts, and used as an ingredient in products like nicotine replacement therapy, e-cigarette liquids, and tobacco-free nicotine products.

Testing for exposure to nicotine detects certain substances in a sample of a person’s urine, saliva, blood, or hair. Depending on the type of test used, nicotine exposure can be detected by testing levels of nicotine, cotinine, and other substances:

• Nicotine testing: Although the amount of nicotine in the body may be measured during testing, nicotine is only detectable in the body for a brief time after exposure and may not be a reliable way to detect nicotine exposure.
• Cotinine testing: Exposure to nicotine leads to measurable levels of cotinine in the blood. Cotinine is a metabolite of nicotine, which means that it’s produced when nicotine is being broken down in the body, primarily by lung, liver, and kidneys. Cotinine remains in the body longer than nicotine, so it is a more reliable test to detect and measure nicotine exposure.
• Other tests: Additional nicotine metabolites that can be measured in the body include trans-3′-hydroxycotinine and nornicotine, although testing for these metabolites is less common. Other substances, such as anabasine, may be measured to help distinguish between tobacco use and use of nicotine replacement therapies.

Nicotine is easily absorbed into the blood following nicotine exposure, leading to increased levels of nicotine and cotinine in the body. There are many ways in which a person may be exposed to nicotine:

• Tobacco products: Tobacco products can be smoked, chewed, or sniffed. Smoked tobacco includes cigarettes, cigars, bidis, kreteks, and the use of loose tobacco in hookahs or pipes. Tobacco products that may be chewed, or sniffed include chewing tobacco, snuff, dip, and snus. Dissolvable tobacco products include lozenges, strips, or sticks that contain nicotine and dissolve in the user’s mouth. Nicotine can also be absorbed through the skin in workers who harvest tobacco and produce tobacco products.
• Secondhand and thirdhand smoke: Secondhand smoke exposure involves inhaling either smoke from the burning end of a tobacco product or smoke that is exhaled by a smoker. Thirdhand smoke exposure occurs when inhaling, touching, or ingesting the residue that’s left on surfaces after smoke clears from the environment.
• E-cigarettes: E-cigarettes, also called vapes, are products that heat a liquid and produce an aerosol that is inhaled by the user. When an e-cigarette liquid contains nicotine, it’s considered an electronic nicotine delivery system (ENDS). ENDS come in a variety of shapes and sizes and may resemble cigarettes, cigars, pipes, pens, or USB sticks.
• Secondhand and thirdhand aerosols: E-cigarettes and other ENDS emit an aerosol that contains nicotine and other chemicals that make up the e-cigarette liquid contained in the device. Secondhand and thirdhand exposure to these aerosols can occur.
• Nicotine replacement therapy: Nicotine replacement therapy (NRT) includes several products that supply users with low doses of nicotine to help reduce withdrawal symptoms during a quit attempt. NRTs include nicotine gum, inhalers, lozenges, nasal spray, and skin patches.
• Tobacco-free nicotine products: Other products that deliver synthetic nicotine to users include nicotine gels, dissolvables, and tobacco-free nicotine pouches. Nicotine gels allow users to absorb nicotine through their skin. Tobacco-free nicotine pouches are filled with a white powder that contains nicotine and is designed to be held between the lip and gums.
• Certain foods: Some foods, such as cauliflower, eggplant, potatoes, and tomatoes, contain naturally-occurring nicotine.

Evidence of nicotine exposure can be detected for a limited time after exposure, called its detection window. The length of the detection window varies based on many factors, including the type, amount and frequency of nicotine exposure. Detection windows can also vary based on the sample used for testing, as well as a person’s race, sex, and genetic makeup.

In general, nicotine can only be detected in the body for a short time, with half of nicotine eliminated in around two hours after a person’s last exposure. Cotinine levels remain elevated for longer, detectable in urine and blood samples for up to 7 days. However, people may continue to have low levels of nicotine and cotinine in their body over time due to secondhand, thirdhand, and environmental nicotine exposure.

When should I get nicotine and cotinine testing?

Nicotine or cotinine testing may be required as part of a smoking cessation program, insurance medical exam, employment testing or to qualify for a surgery or organ transplant. When used to evaluate a patient for nicotine poisoning, a doctor may order testing based on the following symptoms:

• Abdominal cramps
• Agitation and restlessness
• Drooling or burning sensation in mouth
• Tremors or seizures
• Nausea, vomiting, and diarrhea
• Changes in breathing and heart rate
• Headache, dizziness, confusion
• Weakness or paralysis

How to get tested

Nicotine and cotinine testing is often performed in a medical facility or laboratory. Tests can be ordered by a doctor or an administrator of a program that requires nicotine or cotinine testing.

Cotinine tests can also be purchased without a prescription and either conducted at home or prepared at home and mailed to a testing facility.

Can I take the test at home?

At-home drug tests are available to screen for tobacco use and nicotine exposure. While at-home tests that detect nicotine are uncommon, at-home cotinine testing can be conducted on samples of saliva or urine. At-home cotinine test is not a substitute for laboratory testing overseen by a health care professional.

How much does the test cost?

The cost of nicotine and cotinine testing may be covered for by a patient’s employer or the organization requiring the test. Testing may also be covered by health insurance when ordered by a doctor. Patients can talk to their doctor or an administrator at the program requiring testing for additional information about the costs of nicotine and cotinine testing.

The cost of at-home cotinine testing starts around $10.

For laboratory-based testing, samples of urine, saliva, blood, or hair are collected by a health care professional in order to ensure the test’s accuracy.

At-home cotinine test kits provide instructions on collecting a sample of saliva or urine used for testing.

Before the test

Before taking a nicotine or cotinine test conducted by a health care professional, patients should discuss testing procedures with the doctor or staff at the testing location. Procedures for collecting samples may vary based on the reason for testing and the requirements of the test site.

As with other tests, it’s important for patients to discuss any prescription medicines, over-the-counter medications, or supplements they are taking with their doctor.

For at-home cotinine testing, it’s important to read instructions provided in the test kit and prepare materials before collecting a sample.

During the test

For urine drug testing performed in a laboratory, patient’s may be instructed on how to collect a clean catch urine sample. The clean catch method is used to prevent contamination of the sample.

Before a clean catch urine test, patients wash their hands and clean their genitals with a wipe or cloth provided by the health care provider. Patients then urinate into the toilet briefly before placing the collection container into the urine stream. After the container is filled to a pre-marked level, it is moved out of the urine stream as the patient finishes urinating into the toilet

Collecting blood for a nicotine or cotinine test involves having a health care professional draw blood from a vein in the patient’s arm. For testing that requires a sample of saliva, the patient may be asked to spit into a collection device or a pad is placed in the mouth to collect saliva. In hair follicle drug testing, hair samples are usually collected from the scalp, but hair from another part of the body may be collected if the patient doesn’t have sufficient hair on their scalp.

Nicotine and cotinine testing are not painful, although some patients experience temporary discomfort during a blood draw. Samples for testing can often be collected in less than 5 minutes.

Collecting samples of urine or saliva for at-home cotinine testing is similar to the methods used for laboratory-based tests. Once samples are collected, at-home cotinine tests require patients to use a test strip or other device to test the sample for the presence of cotinine.

Test devices vary, so it’s important to read the instructions provided in the test kit before testing the collected sample.

After the test

After collecting a sample for laboratory-based urine testing, patients seal the collection container and return it to the health care provider at the testing facility. After samples of saliva, blood, or hair are collected by a health care provider, no additional actions are required from the patient.

There are no restrictions on activity after sample collection for nicotine and cotinine testing.

Receiving test results

The results of nicotine or cotinine testing may be available within a few minutes to a few days, depending on the method and reason for testing. Patients may learn about their test results through a doctor, other health care provider, or an administrator of the organization requiring nicotine and cotinine testing. Test results may also be received electronically or in the mail.

Results of at-home cotinine tests are usually available within minutes of conducting the test. Patients should consult the test instructions for information on how long to wait before interpreting test results.

Interpreting test results

The results of nicotine and cotinine testing indicate whether or not nicotine or cotinine were found in a patient’s sample and may include information about the amount of nicotine or cotinine detected.

When interpreting test results, it’s important to keep in mind that nicotine and cotinine tests are either qualitative or quantitative. The results of qualitative nicotine or cotinine tests are interpreted differently than the results of quantitative tests:

• Qualitative nicotine and cotinine tests:  Qualitative testing shows whether nicotine or cotinine was found in the sample, but not the amount of these substances. At-home cotinine tests are a type of qualitative testing.
• Quantitative nicotine and cotinine tests: Quantitative testing measures the amount of nicotine and cotinine in the body. Quantitative testing is only available in laboratory-based testing conducted by a healthcare professional.

Positive test results indicate that sufficient nicotine or cotinine was detected in the sample to meet the test or laboratory’s cutoff value for a positive result.

A negative test result means that insufficient nicotine or cotinine was detected in the sample for a positive result. This result can occur because the patient hasn’t used tobacco or been exposed to nicotine, because nicotine exposure was outside of the detection window, or because the level of nicotine detected was too low for a positive result.

The cutoff values for a positive test result, also called the tests reference range, are not standard between laboratories and vary based on the purpose of the test, the type of test sample, and the individual laboratory or at-home testing kit.

Are test results accurate?

While no test is perfect, nicotine and cotinine tests are commonly used to detect nicotine exposure. In order to reduce the risk of false-positive results, laboratories attempt to create cutoff levels that reduce the likelihood of a positive test result after exposure to nicotine through secondhand smoke, thirdhand smoke, or other environmental exposures.

When reviewing test results, patients may find it helpful to ask their doctor about the reference ranges used to determine a positive result, the likelihood of a positive result due to environmental nicotine exposure, and the reliability of nicotine and cotinine testing.

Questions for your doctor about test results

Patients may find it helpful to ask questions about nicotine and cotinine test results. Questions for a patient’s doctor can include:

• What substance is being tested?
• What is my test result?
• Is my test result able to distinguish between tobacco use and secondhand, thirdhand, and environmental nicotine exposure?
• Who will have access to my test result or medical record?