Nicotine quickly enters your bloodstream. Your liver then breaks down nicotine into several byproducts, primarily cotinine. Depending on what you’re testing, such as a blood, urine, saliva, or hair sample, nicotine and its byproducts may be detectable from a few hours to several months after use.

Nicotine doesn’t generally stay in your system very long. It has a half-life of two hours, which means half of it is gone from your bloodstream about two hours after use. But cotinine and other tobacco byproducts tend to stay in your system longer, though exactly how long may vary from person to person.

In general, nicotine and cotinine can remain in your body for a few hours to several days. In some cases, traces may be detectable beyond that. For example, some tests, like those using hair or certain urine markers, can detect signs of nicotine use for weeks or months after your last exposure.

How long nicotine stays in your body depends on several factors, including what kind of nicotine product you use, how often you use it, and how your body processes it.

Several factors affect how quickly your body processes nicotine. These include:

• Genetics: People with certain gene variations may process nicotine more slowly or quickly than others. Those with a slower metabolism due to genetics tend to keep nicotine in their system longer.
• Age: As you get older, your body processes nicotine more slowly, but this effect can vary.
• Sex: Due to hormonal effects, women, especially those who are pregnant or taking estrogen-containing birth control, tend to clear nicotine faster than men.
• Body mass: Your weight and body mass index (BMI) can affect how your body distributes and processes nicotine. But body weight itself doesn’t have a big impact on how quickly nicotine leaves your system.
• Frequency of use: Regular, frequent smokers tend to build up higher levels of nicotine and cotinine in their bodies, which can take longer to clear out compared to people who use tobacco occasionally.
• Type of tobacco product: Different tobacco products deliver varying amounts of nicotine. Nicotine stays in the blood longer with smokeless tobacco.

Most tests don’t look for nicotine itself, but for cotinine or other related substances. How long nicotine is detectable in your body depends on what type of sample you test and what you’re testing for.

• Blood sample: In blood, nicotine is usually gone within a few hours due to its short half-life. But cotinine can be found in your blood for up to three to four days.
• Saliva sample: Cotinine can typically be found in saliva for up to four days after your last exposure to nicotine.
• Urine sample: Urine tests may detect nicotine or related substances for up to eight weeks, some research suggests.
• Hair sample: Hair grows slowly, which means you can detect nicotine in it for weeks, months, or even years after exposure. These tests are used to spot long-term nicotine use, but hair can sometimes pick up secondhand smoke exposure.

The most effective way to clear nicotine from your body is to stop using all tobacco and nicotine products. If you need to pass a nicotine test, these strategies may be helpful:

• Wait it out: Time is ultimately the most reliable factor in clearing nicotine from your system. Plan for at least a few days of nicotine-free time before a blood or saliva screening, and longer for urine or hair testing.
• Exercise: Boosting your metabolism through exercise may help your body eliminate nicotine faster, though it doesn’t make it disappear instantly. High-intensity interval training (HIIT) and resistance training may help the body burn fat and boost metabolism.
• Eat antioxidant-rich foods: Antioxidants help neutralize harmful substances and support metabolic function. People who take in more antioxidants, especially vitamins AC, and E, zinc, selenium, and carotenoids, tend to have lower cotinine levels. Consider carrots, sweet potatoes, spinach, berries, citrus fruits, and nuts.
• Avoid more nicotine: Using nicotine replacement products like patches or gum will still put nicotine in your system, even though they may help you quit smoking. If you’re trying to pass a nicotine test, you’ll need to avoid all nicotine and tobacco products.

When you stop using nicotine, your body and brain have to adjust. That can lead to a range of physical and emotional withdrawal symptoms, especially if you’ve used nicotine regularly. While it’s a sign that your body is healing, withdrawal can be uncomfortable.

Common nicotine withdrawal symptoms include:

• Strong nicotine cravings
• Irritability, anger, or frustration
• Increased anxiety
• Low mood or mild depression
• Trouble focusing or concentrating
• Trouble sleeping
• Feeling restless or jittery
• Feeling hungrier than usual

Most people find that nicotine withdrawal symptoms are strongest in the first week after quitting, when cravings are most intense. Symptoms gradually decrease over time. Many physical symptoms improve within a few weeks, though others, like occasional cravings, may persist for months.

How To Manage Withdrawal

Nicotine withdrawal symptoms are temporary, and the health benefits of quitting begin almost immediately. To manage withdrawal symptoms, these approaches may help:

• Consider nicotine replacement therapy: Nicotine patches, gums, or lozenges provide small, controlled amounts of nicotine. These products can reduce physical withdrawal symptoms.
• Talk to a healthcare provider about prescription medications: Some people find prescription medications like Zyban (bupropion SR) or Chantix (varenicline) helpful.
• Stay busy: Staying active, drinking plenty of water, practicing deep breathingand finding healthy distractions can help manage cravings.
• Find support: Having a support system, such as friends, family, or a smoking cessation program, can help you work through discomfort and stay focused on your goals.

Nicotine and cotinine (a nicotine byproduct) stay in the body for a few hours to several days, sometimes even longer.

Blood and saliva tests usually detect nicotine and cotinine for a few days, while urine tests may pick them up for weeks. Hair tests have the longest window, sometimes showing nicotine use months after your last exposure.

The exact timeframe varies based on factors, including your genetics, age, sex, how often you smoke, and the type of tobacco or nicotine products you use.