Nicotine & Cotinine Test: Levels, Uses, Symptoms & Complete Guide

Overview

The Nicotine Test, often referred to as the Nicotine/Cotinine Test, is a laboratory test that measures either nicotine or cotinine (its main breakdown product) in the body. Nicotine is a highly addictive chemical found in cigarettes, cigars, chewing tobacco, gutka, bidi, hookah, and e-cigarettes. When nicotine enters the bloodstream, the liver breaks it down into cotinine, which stays in the body much longer. Because of this, cotinine is considered the most accurate and reliable marker for identifying tobacco use and secondhand smoke exposure.

This test is commonly used to:

• Check active smoking
• Detect passive smoke exposure
• Monitor smoking cessation programs
• Evaluate patients before surgery
• Verify tobacco abstinence for insurance purposes

What Is Nicotine?

Nicotine is a natural chemical found in the tobacco plant. It acts as a stimulant and creates addiction by triggering dopamine release in the brain. People commonly absorb nicotine through:

• Smoking cigarettes, bidis, cigars
• Chewing tobacco, gutka, paan masala
• Vaping e-liquids containing nicotine
• Secondhand smoke

Nicotine reaches the bloodstream within seconds of inhalation. The liver converts it into cotinine, which can be detected for 1–10 days, depending on use.

Where Is Nicotine Produced in the Body?

Nicotine is not produced inside the body. All nicotine comes from external sources:

• Tobacco smoke
• Vaping aerosols
• Chewing tobacco
• Snuff or gutka
• Secondhand smoke
• Nicotine replacement therapy (patches/gums)

Once absorbed, the liver metabolizes nicotine into cotinine, which circulates in the blood and is later excreted through urine.

Main Functions & Importance of the Nicotine/Cotinine Test

Nicotine has no beneficial role in the human body.

It is not required for any physiological process. Instead, it acts on nicotinic acetylcholine receptors, stimulates dopamine release, and creates addiction.

The test is clinically important because it helps in:

✔ Confirming Tobacco or Nicotine Use

Determines if the person is smoking or has been recently exposed.

✔ Differentiating Active Smokers vs. Passive Smokers

Cotinine levels can identify secondhand smoke exposure.

✔ Pre-Surgery Screening

Surgeons require nicotine-free status because nicotine affects healing.

✔ Insurance Evaluation

Many insurance companies check cotinine levels before issuing policies.

✔ Monitoring in De-addiction & Quitting Programs

Helps track progress in people trying to quit smoking.

Causes of Low or Negative Levels

A low or negative nicotine/cotinine result may happen due to:

• No tobacco use
• Very minimal exposure
• Successful smoking cessation
• Many days have passed since last use
• Use of nicotine-free vaping liquids
• Diluted samples (rarely)

Symptoms of Low or Negative Levels

Nicotine is not needed by the body, so low levels cause no medical symptoms.

However, smokers who recently quit may feel:

• Irritability
• Restlessness
• Cravings
• Mood changes
• Anxiety

These are due to withdrawal, not low nicotine levels.

Causes of High or Positive Levels

High levels of nicotine or cotinine indicate significant exposure.

Common Causes:

✔ Active Smoking

Cigarettes, cigars, bidis, hookah, pipe tobacco.

✔ Smokeless Tobacco Use

Gutka, khaini, paan masala with tobacco, chewing tobacco, snuff.

✔ Vaping with Nicotine Liquids

✔ Nicotine Replacement Therapy

Patches, gums, lozenges, sprays (raises cotinine levels).

✔ Secondhand Smoke Exposure

Leads to detectable but lower cotinine levels.

✔ Occupational Exposure

Tobacco industry workers.

Symptoms of High Nicotine Levels

Short-Term Symptoms

• Fast heartbeat
• High blood pressure
• Dizziness
• Nausea or vomiting
• Increased alertness
• Headache

Long-Term Symptoms

• Anxiety
• Addiction
• Restlessness
• Poor sleep
• Decreased appetite

Chronic Exposure Risks

High nicotine intake for long periods increases the risk of:

• Heart disease
• Stroke
• Lung diseases
• Certain cancers
• Poor wound healing

Reference Ranges (May Vary by Lab)

Blood Nicotine Levels

• 0–2 ng/mL → Non-smokers
• Above 10 ng/mL → Active smokers

Blood Cotinine Levels

• <10 ng/mL → Non-smoker
• 10–100 ng/mL → Light smokers or passive exposure
• >300 ng/mL → Regular/active smokers

Urine Cotinine Levels

• <50 ng/mL → Non-smoker
• >200 ng/mL → Active smoker

Cotinine is the preferred marker due to its longer half-life.

Sample Types Used

Doctors may request:

✔ Blood (Serum or Plasma)

Used for exact quantitative measurement.

✔ Urine (Most Common)

Best for screening — high accuracy & easier collection.

✔ Saliva

Good for detecting recent exposure.

✔ Hair Sample

Useful for long-term exposure detection (months).

Nicotine/Cotinine Test – Why It Is Done

Doctors order this test for:

• Tongue/Throat/Lung problems in smokers
• Pre-surgery screening
• Insurance policy evaluation
• Confirming relapse in quitting programs
• Suspected poisoning
• Detecting exposure in children around smokers
• Verifying claims of being smoke-free

Test Preparation

• No fasting required
• Avoid smoking or vaping before sample collection (unless testing intentionally)
• Inform doctor about nicotine patches or gums
• Drink normal amount of water
• Do not dilute urine sample intentionally

When to Consult a Doctor

Contact your doctor if you experience:

• Persistent cough
• Shortness of breath
• Chest pain
• High blood pressure
• Severe withdrawal symptoms
• Strong cravings that you cannot control
• Difficulty quitting smoking

Nicotine addiction may require medical or behavioral support.

Important Word Explanations

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