The First 24 Hours After Quitting Smoking
A clear UK guide to the first 24 hours after quitting smoking, what happens in your body and how to get through it.
The short answer
Fast recovery. Your body starts healing within twenty minutes of your last cigarette.
Key change
Carbon monoxide clears and oxygen levels rise.
Expect
First cravings as nicotine leaves your system.
The first 24 hours after quitting smoking
The first day is when your body begins to bounce back. Within twenty minutes your heart rate and blood pressure start dropping, carbon monoxide clears over the following hours so oxygen levels rise, then by the end of the day your risk of heart attack already begins to fall. The early healing is rapid.
It helps to know what is happening inside, since it turns an anxious day into an encouraging one. The first cravings tend to arrive too, though they pass, with knowing the timeline making them easier to ride out. This page walks through what happens hour by hour, what you may feel and how to get through the first day.
Let us look at the changes, what you may feel and how to cope.
The first day can feel like the biggest hurdle, though it is also when the rewards start to stack up fastest. Seeing it as the day your body begins to repair, rather than just a day of going without, can shift how the whole thing feels.
What happens in your body
A lot changes in a single day. Within twenty minutes your heart rate and blood pressure ease, within several hours the carbon monoxide in your blood falls so more oxygen reaches your organs, then within a day your nicotine level drops toward zero and your heart attack risk starts to decrease.
- Within 20 minutes: heart rate and blood pressure begin to drop.
- Within a few hours: carbon monoxide falls and oxygen levels rise.
- Around 12 hours: carbon monoxide returns toward a normal level.
- By 24 hours: nicotine clears and heart attack risk starts to fall.
Carbon monoxide matters more than people realise. This gas in cigarette smoke crowds out oxygen in your blood, so as it clears in the first day your heart no longer has to work as hard and more oxygen reaches your body, which is a real early win.
You will not feel the carbon monoxide clearing directly, though it is one of the quickest and most meaningful changes happening behind the scenes. Within the first day your blood is already carrying oxygen the way it should, which supports your heart, muscles and brain.
The first day, hour by hour
Illustrative timeline, varies by person.
What you may feel
The first day brings feelings as well as changes. As nicotine leaves your system you may notice your first real cravings, along with some restlessness or irritability, which is normal and a sign your body is starting to adjust, rather than anything to worry about.
Cravings tend to come in waves and each one passes within minutes, even though it can feel strong in the moment. You might feel a little on edge or find your hands looking for something to do. None of this is dangerous, since it is the very start of breaking free from nicotine. Reminding yourself that the discomfort is temporary, while your body is already healing, helps you stay the course through day one.
It is worth being a little kind to yourself on this first day too. You are asking a lot of your body and mind, so a slower, simpler day with fewer demands can make the cravings easier to handle while the early changes get under way.
Getting through day one?
Switching to vaping is far less harmful than smoking and gives you something to reach for. Browse the range or ask our team.
How to get through the first day
A few simple things carry you through. Keep busy, drink plenty of water, stay active, avoid your usual smoking triggers and use nicotine replacement or vaping to take the edge off, since each craving passes in a few minutes.
It helps to plan the day a little, filling the moments you would normally smoke with something else, like a short walk or a cup of tea somewhere you cannot light up. Keeping your hands and mouth busy makes a difference, as does reminding yourself why you are doing this. Leaning on friends, family or a stop smoking service gives you backup if a craving feels strong. Getting through the first 24 hours is a real achievement, plus it sets you up for the days ahead.
- Keep busy: fill the moments you would usually smoke.
- Stay hydrated and active: water and a walk both help.
- Avoid triggers: steer clear of your usual smoking cues today.
- Use support: nicotine replacement, vaping or a stop smoking service.
If you want to dig deeper, see our explainer on how quitting affects your heart. It pairs well with our guide on how long nicotine takes to leave your body and our look at the first week after quitting.
For the full set of guides, the quit smoking hub brings everything together in one place.
The bottom line: in the first 24 hours after quitting smoking your body starts healing quickly. Within twenty minutes your heart rate and blood pressure ease, carbon monoxide clears over the following hours so oxygen levels rise, then by the end of the day your nicotine level drops and your heart attack risk begins to fall. You may notice your first cravings, which pass in minutes. Keep busy, stay hydrated and lean on support to get through.
Through the first day?
Switching from smoking to vaping is far less harmful and gives you something to reach for. Our vape starter kits make it simple. You can also speak to the Vape Chaos team, plus a stop smoking service.
Frequently asked questions
What happens in the first 24 hours after quitting smoking?
Your body starts healing quickly. Within twenty minutes your heart rate and blood pressure begin to drop. Over the following hours carbon monoxide clears from your blood so more oxygen reaches your organs. By the end of the day your nicotine level drops toward zero and your risk of heart attack begins to fall. You may also notice your first cravings.
Why does carbon monoxide matter when I quit?
Carbon monoxide is a gas in cigarette smoke that crowds out oxygen in your blood, so your heart has to work harder to supply your body. As it clears in the first day after quitting, oxygen levels rise and your heart no longer has to work as hard. This is one of the first real wins your body notices after stopping.
Will I get cravings in the first 24 hours?
Yes, the first real cravings often arrive within the first day as nicotine leaves your system. They tend to come in waves and each one passes within minutes, even though it can feel strong in the moment. You may also feel a little restless or irritable. This is normal and a sign your body is starting to adjust, not anything to worry about.
How do I get through the first day without smoking?
Keep busy and fill the moments you would normally smoke with something else, like a short walk or a cup of tea somewhere you cannot light up. Drink plenty of water, stay active, avoid your usual triggers and keep your hands busy. Nicotine replacement or vaping can take the edge off, plus a stop smoking service offers support if cravings feel strong.
Is feeling restless in the first 24 hours normal?
Yes, feeling restless, on edge or irritable as nicotine leaves your system is a normal part of the first day. It is uncomfortable but not dangerous, since it is the very start of breaking free from nicotine. Reminding yourself that the discomfort is temporary, while your body is already healing, helps you stay the course through day one.
It is worth being a little kind to yourself on this first day too. You are asking a lot of your body and mind, so a slower, simpler day with fewer demands can make the cravings easier to handle while the early changes get under way.
