After quitting tobacco, it takes 1 to 3 days for nicotine to clear from the blood system and up to 10 days for cotinine to get excreted from the body. This is only an estimate as people process nicotine differently depending on their genetics and lifestyle. It also depends on your consumption and the nicotine level in your cigarettes or vapes.

Cotinine is also quite often tested along with the nicotine test. It is the main metabolite of nicotine and has more pharmacological effects, though more research is required. Cotinine is tested more as it is stable than nicotine, and lasts longer in the body. It is found in the body only when you have use nicotine products.

How Long Does Nicotine Stay in Your Body?

Though there are many factors for the nicotine to remain in the body, it generally leaves within 24 hours of your stoppage of tobacco use. However, its byproducts remain in the body for a long. Your body absorbs tobacco if you smoke, vape, or chew. Though you no longer feel its effect, nicotine and its byproducts are traceable in the body. 

When you consume tobacco, your liver breaks nicotine into a substance called cotinine before all traces removes via urine. Studies indicate blood nicotine levels drop by 50% in 2-8 hours. Cotinine might also take around 16 hours to drop by 50%. However, a 2016 review suggests it might take up to 40 hours to reduce by 50%. It is due to this reason clinicians believe that measuring different cotinine levels is best to determine tobacco levels.

Half-Life of Nicotine

Nicotine has a half-life of around two hours. A drug’s half-life is the time it takes for half of the dosage administered to get eliminated from the body. When anyone smokes a cigarette or uses a vape, it gets absorbed through the lungs and directly into the blood stream. At the very least, it is absorbed through mouth and throat membranes. If you chew tobacco or use nicotine gum, patches, or lozenges nicotine gets absorbed through the mucous membranes in the mouth. Some nicotine gets excreted by the kidneys via urine, but some through feces. Level of Nicotine is also found in saliva and hair.

Nicotine in Blood 

Nicotine can be detected in blood tests, and so are its metabolites, including cotinine and anabasine. It might remain in the blood for 48 hours and cotinine for three weeks. After blood tests, it might take two to ten days to get the results.

Nicotine in Saliva

Nicotine remains in saliva for around 11 hours and in extensive smokers for 4-5 days. It is considered one of the best nicotine tests that are preferred these days. Cotinine can remain for seven days after the last day of use and up to 14 days in heavy smokers. The technician swabs the inside of your mouth and tests oral fluids for nicotine, and its results can take 24 to 72 hours.

Nicotine in Hair 

Hair follicle testing is conducted to detect nicotine and is done for much longer. This method is not very common, as is more expensive. A single strand of hair is removed and tested in the lab for repeated nicotine use over the last 90 days. Results can take one to five days.

Nicotine in Urine 

Once a person stops using tobacco products, nicotine, and cotinine will start excreting through urine in 3 to 4 days. Cotinine remains in urine for longer in people who smoke menthol cigarettes and in those exposed to second-hand smoke from menthol cigarettes.

Nicotine in Breast Milk 

Nicotine enters breastmilk in high concentrations through smoke, but its quantity can get reduced to half in two hours. However, the period it remains there is for ten days.

Factors That Affect Detection Time in Nicotine

The time nicotine remains in the system at a delectable level largely depends on the type of test conducted. As each body consumes nicotine differently, it is impossible to determine the detection time frame with 100% confidence. 

Age 

As you age, it gets difficult for the body to excrete nicotine which allows it to remain in your system for a long.  Your metabolism slows down as you get older and this is the biggest proponent to that.

Body mass

Nicotine is stored in fatty tissue. The more body fat in your body, the longer you will have positive nicotine level.

Genetics

Studies have found that a person’s genetic makeup can also affect the nicotine metabolism rate.

Hydration Level

Drinking water can also increase the secretion of nicotine. It's best to stay hydrated.

Physical activity 

As skin helps in the excretion of metabolic waste products, so with the increase in sweating during physical activity, there is an increase in excretion rate. 

How Do Nicotine Tests Work?

Nicotine tests are either qualitative or quantitative. Quantitative tests tell whether you are an active smoker or have recently quitted and also exposure to secondhand smoke if you are not a tobacco user.

Who Requires Nicotine Tests?

Nicotine tests are not commonly conducted but might require you to do the following:  

• Before surgery 
• It is needed as a piece of evidence by the court in the child custody case 
• You give tests during the time applying for a job 
• It is conducted for smoking cessation programs 
• If your doctor suspects you have a nicotine overdose 
• When you have applied for health or life insurance.

What Do The Results Mean? 

No nicotine content was found, which means there is hardly any exposure for weeks, which includes secondhand smoke exposure. 

Little Quantity of Nicotine Detected

Exposure to secondhand smoke or use within the last week but not in the last few days. In this case, very little nicotine was detected. 

This result indicates the detection of a moderate level of nicotine. This means a person is not smoking for the last few days.

Why Test for Nicotine? 

Testing for nicotine is done to meet many objectives: 

For Health assessments

Testing can help assess an individual's level of tobacco intake and exposure, which can determine many different health issues like lung cancer, heart disease, and stroke.

Tests To Hire Employees

Many employers conduct drug testing as a condition to hire employees. It is to promote a proper and healthy workplace, reduce healthcare costs, and improve productivity.  

Insurance

Some life insurance companies also might require testing as a part of the underwriting process. It can increase the risk for health conditions which might impact insurance premiums. 

Smoking cessation program

Testing can also be used to monitor progress in quitting smoking. It helps track nicotine levels. health care providers can assess the impactfulness of smoking cessation interventions and tailor plans to meet individualistic needs.

Testing for nicotine can provide information for both medical and non-medical purposes

Nicotine levels in the blood will continue to decline within around 2 hours, especially reaching zero after 24 hours, However, nicotine traces and its byproducts can get detected for days and even for weeks, while testing saliva, urine, or hair. The speed at which the body clears, nicotine might vary depending on many different factors like age and dosage. You might face withdrawal while stopping nicotine, But it is and its byproduct cotinine remains even if you are not feeling the effects. The best is to consult your doctor.