Mucolytics are medications that providers use to treat chronic lung and breathing conditions. They break up mucus in your lungs and make it easier to cough out. They’re most commonly used in a nebulizer to treat cystic fibrosis or bronchiectasis. The most common side effects include stomach upset and voice changes.


What is a mucolytic?

Mucolytics are medications that break up mucus so you can clear it out of your lungs more easily. They’re used to treat cystic fibrosis, bronchiectasis and other lung conditions. They come in oral, intravenous (IV) and nebulizer forms.

Mucolytics are part of a more general group of medications called mucoactive agents. Mucoactive agents have various ways of removing mucus from your lungs. They might break up mucus, thin it out or allow it to move more easily from your lungs. Other mucoactive agents include expectorants, mucoregulators and mucokinetics.

What conditions do mucolytics treat?

Providers use mucolytics to treat chronic (long-lasting) lung or breathing conditions that create thick mucus. These include:


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What are examples of mucolytic drugs?

Acetylcysteine (also called N-acetyl cysteine, N-acetyl-L-cysteine or NAC) and dornase alfa are mucolytic drugs. Brand names include Mucomyst® and Pulmozyme®.

Both types of mucolytics break apart mucus in your lungs. NAC also has anti-inflammatory and antioxidant properties. It can also treat an acetaminophen (Tylenol®) overdose.

Dornase alfa isn’t recommended for non-cystic fibrosis bronchiectasis.

Procedure Details

How do mucolytics work?

When your lungs are working as they should, mucus traps irritants and infectious particles (like bacteria or viruses). Hairlike structures in your lungs (cilia) help you clear out the mucus — and all the things trapped in it — when you cough.

But certain chronic lung conditions create a lot of thick, hard-to-clear mucus. This can make it hard to breathe and trap germs in your lungs, causing you to get sick more easily. Mucolytics break apart the molecules that make up mucus, making it thinner and easier to clear out of your lungs.


How do you take mucolytics?

You often get a mucolytic as a liquid that you put in a nebulizer machine. You breathe in the medication as a mist. Providers can also give them in an IV into a vein, or you can take them as a pill you swallow.

Risks / Benefits

What are the benefits of mucolytics?

If you have a chronic lung condition with thick mucus, mucolytics make it easier to breathe and reduce your risk of infection. People with cystic fibrosis or bronchiectasis may have a better prognosis when they’re better able to clear their lungs. Providers sometimes use them to treat COPD or emphysema when symptoms get worse (exacerbate).


What are the risks or side effects of mucolytics?

Acetylcysteine can cause bronchospasm, so people with asthma should be careful when taking it. Side effects of mucolytics include:

And while not harmful, many people notice that acetylcysteine smells very bad.

Do mucolytics make you cough more?

Mucolytics make it easier to clear mucus out when you cough. They don’t necessarily make you cough more.

When To Call the Doctor

When should I call my healthcare provider?

Contact your healthcare provider if you:

  • Have any questions or concerns about mucolytic treatment.
  • Have any unwanted, unexpected or severe side effects to your treatment.
  • Feel like your treatment isn’t working.

Additional Common Questions

Which is better, mucolytic or expectorant?

Mucolytics and expectorants, like guaifenesin (Mucinex®, Robitussin®), work in different ways to clear mucus out of your lungs. Mucolytics treat chronic lung or breathing conditions. They usually require a prescription from a provider. Expectorants are more widely available over the counter (OTC) and are usually used to treat more common conditions, like cold and flu symptoms.

A note from Cleveland Clinic

Mucolytics can give you relief from the symptoms of chronic lung diseases and improve your quality of life. Talk to your provider about any questions you have about mucolytic medications. They can address your concerns and recommend treatments for any possible side effects. They’ll work with you to find the treatment that’s the best fit for you.

Medically Reviewed

Last reviewed on 04/13/2023.

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