Cotinine

General Information

Nicotine is an addictive chemical found in the tobacco plant and concentrated in its leaves. Nicotine is metabolised by the liver into more than 20 compounds, which are removed by the kidneys into the urine. Tobacco use and exposure to tobacco smoke can increase nicotine concentrations in the body. Cotinine is the body's main breakdown product (metabolite) of nicotine. Cotinine and nicotine levels also rise with use of nicotine replacement products such as nicotine patches and gums. In large amounts, nicotine is poisonous.

Cotinine is usually the best test to check for tobacco use or exposure to tobacco smoke because it lasts longer in the body and is only produced when nicotine is metabolised. 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 are usually requested instead of nicotine tests.

Cotinine may be requested whenever an evaluation of tobacco use status or tobacco smoke exposure is required. When someone enters a smoking cessation programme, urine cotinine tests may be requested to evaluate compliance. Urine testing may be performed as a screen for tobacco use when someone is applying for life or health insurance, or applying for work with an employer that prohibits smoking.

Cotinine are occasionally measured when a patient has symptoms that the doctor suspects may be due to a nicotine overdose. Symptoms of nicotine poisoning may include:

• Feeling sick
• vomiting
• Dizziness
• Drooling
• Weakness

If you require urgent measurement please contact the duty toxicologist on bleep 3289