How Long Do You Cough Up Phlegm After Quitting Smoking?

Most people, quite rightly, associate smoking with damage to the lungs and your health in general.

Long-term smoking will cause permanent damage to the lungs in the form of emphysema and chronic bronchitis, which together make up a common condition known as chronic obstructive pulmonary disease (COPD). 

Therefore, it can take some people by surprise that a possible side-effect of quitting smoking is coughing, including coughing up phlegm.

You’d have thought that quitting smoking would improve your lung health, and a cough isn’t exactly a sign that your lungs are healthy. 

You’re probably wondering if it’s normal to develop a phlegmy cough after you quit smoking, and you’re definitely wondering how long it’s going to go on for if you’re suffering from one.

Thankfully for you, you’ve come to the right place for answers to those questions. Let’s get started!

Is It Normal To Cough Up Mucus After Quitting Smoking?

Although it’s not a common side effect of smoking cessation, some people do report developing a cough in the early days of quitting. It can be a worrying development for people who are quitting, who may naturally wonder if something serious is going on.

By understanding it, you can ease those fears and make quitting easier. Thankfully, this cough is usually temporary, and is in fact a sign that the body is beginning to heal. 

Why Does Quitting Smoking Cause A Cough?

The reason that some people develop a cough after quitting smoking is all down to tiny hair-like Cilia that can be found on the surface of cells in your airways.

Cilia are there to protect your lungs from pollutants- your bronchial tubes are lined with a thin coating of mucus and cilia.

The Cilia sway side-to-side in unison, acting almost like a brush to sweep pollutants that have been trapped in the mucus out of your lungs. One said mucus reaches the throat, it can be coughed out as phlegm or swallowed. 

The thousands of harmful chemicals in cigarette smoke damage the cilia and stop them from performing their vital cleaning function.

This is because they become caked in a sticky build-up of tar, which paralyzes them and stops them from sweeping out irritants and pollutants.

When you stop smoking, the body begins to heal as soon as you have extinguished your last cigarette. This includes the cilia, which gradually begin to resume their function of cleaning the trapped pollutants and toxins out of your lungs. 

That’s why you develop the cough after you’ve finished smoking. Whilst you were smoking, your cilia had been effectively disabled and were unable to shift mucus out of your lungs.

Upon quitting, that function returns, bringing with it the telltale phlegmy cough. It might be frustrating in the early stages of smoking cessation, but don’t worry- think of it as a sign of your progress!

Your lungs are beginning to undo the damage that smoking had done to them. 

How Long Do You Cough Up Phlegm After Quitting Smoking?

Every person’s body is different, and the speed at which your lungs recover- and therefore how quickly you recover from your cough- is largely dependent on how much you smoked and how long you smoked for.

Obviously, heavier smokers who have smoked for a long time will notice that it takes longer for their lungs to recover than someone who was a light smoker or who had only started recently. 

In general, the phlegmy cough should improve with time, and within a few weeks to a month it should clear up entirely. However, a cough and shortness of breath may linger on for longer, slowly improving over the course of a year or so. 

What Can I Do To Improve My Cough? 

Whilst your cough will still take some time to clear up, there are a couple of things you can do to help ease your symptoms and speed the process along.

The easiest and most effective way to do this is to keep well hydrated by drinking plenty of water. You can also drink tea, and teas that contain licorice root are a particularly good choice as licorice acts as a natural throat soothing expectorant. 

If you find your throat is particularly sore and irritated, you could try using standard remedies like cough syrup or a tablespoon of honey a few times a day.

You could also use throat soothing lozenges. If you live in a particularly cold environment or the weather has been particularly dry of late, you could even consider using a humidifier in your home.

The extra humidity in the air will help to loosen up the mucus in your throat, encouraging a more productive cough that should see you expel the mucus from your lungs more quickly. 

When Should I Start To Worry?

As we’ve said, whilst developing a cough in the early stages of quitting smoking isn’t all that common, it’s nothing to worry about.

However, there are a few symptoms that you should watch out for that may indicate something more serious than the recovery of the lungs:

  • Coughing up blood- This could be a sign of an infection, or could be an early warning sign of lung cancer.
  • Wheezing- If you’re breathing noisily, it’s likely that your airways are inflamed and constricted.
  • Shortness of breath- Struggling to breathe, especially after little or no exertion, is a worrying sign. 

If you’re suffering from any of these symptoms, please see a doctor as soon as possible.


It is quite normal to develop a phlegmy cough in the early stages of smoking cessation, and it’s nothing to worry about. In fact, it’s a sign that your lungs are healing and their cleaning processes are kicking back into action.

The cough typically lasts a few weeks, though it may take longer to clear up if you were a particularly heavy long-term smoker.

However, if you notice a deterioration in your condition, or for example find yourself coughing up blood, please seek medical attention as soon as possible. 

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