Continuous positive airway pressure (CPAP) therapy is the standard treatment for obstructive sleep apnea (OSA). Interestingly, OSA shares various features with asthma. This makes CPAP a possible therapy, particularly if a person has both asthma and OSA.

We’ll discuss how CPAP machines work, how they may help with various breathing problems, and what side effects you might experience while using one.

A CPAP machine is connected by a tube to a mask that fits over your nose or mouth. Its purpose is to blow air into your airway while you sleep. CPAP machines are not a stand-alone treatment for asthma specifically. They are also not intended to treat asthma exacerbations, also known as asthma attacks.

That said, 2019 research suggests that OSA and asthma are closely linked. According to a 2016 review, the prevalence of the two conditions ranges from 38 to 70 percent. Some researchers even refer to the two conditions as overlapping. This may be because they share risk factors, or because they produce similar issues in the upper and lower airways.

Your doctor will only suggest using a CPAP machine if you have OSA. If you have asthma but not OSA, your doctor may suggest trying other asthma treatments, like inhalers, oral medications, injections, or infusions.

Yes. According to a 2018 review, untreated OSA can worsen your asthma symptoms by further narrowing the bronchial tubes and increasing inflammation in the airways. People who have OSA and asthma may also have:

  • less control over their asthma
  • more asthma symptoms at night
  • more frequent asthma attacks

In general, people with asthma are at a higher risk of developing OSA than people who do not have asthma. And even without a diagnosis, people with asthma tend to report OSA symptoms like snoring, sleepiness in the day, or apnea more than people who do not have asthma.

If you have asthma and have issues with breathing, snoring, frequent night wakings, or excessive daytime sleepiness, it may be worth making an appointment with your doctor to see if there’s a connection. Treatment for OSA can help with both conditions.

CPAP machines treat OSA by providing a constant stream of air to the airways. This continuous pressure keeps airways open and reduces symptoms like snoring and apnea, or pauses in breathing.

According to a 2018 review, CPAP may help with asthma by:

  • promoting better nighttime sleep
  • lessening inflammation
  • reducing reflux episodes
  • improving the function of the lower airways

It may take a few nights to get used to using a CPAP machine. Some people may even find the mask to be claustrophobic or uncomfortable.

You may also experience some side effects after using a CPAP machine, like:

Adding a humidifier to your room can help with nosebleeds and other issues related to dry air. If you are having trouble getting used to your machine, your doctor may be able to suggest a different type of mask, like nose-only or full face shield. Or they may suggest mask padding, depending on what makes you most comfortable.

Can a CPAP machine make asthma worse?

As mentioned, people who use CPAP machines may develop unpleasant symptoms from breathing in dry air. If you have asthma, you may notice that breathing in dry air overnight makes your airways irritated or swollen, increasing symptoms or causing asthma attacks.

If dry air affects your symptoms, speak with your doctor about adding a humidifier to your machine to moisturize the air.

Your doctor is your best resource for how to use your CPAP machine and mask. They can help determine what airflow pressure is best for you.

Some tips for usage:

  • Wear your mask during all nighttime sleep and daytime napping for the best results.
  • Consider using timed pressure ramp settings. These settings will start pressure on low and then slowly adjust to your desired level for comfort.
  • Try using a humidifier chamber if you deal with dry mouth, nosebleeds, or other related issues.
  • Follow up with your doctor to make sure you’re using the machine correctly, check that your mask fits appropriately, and troubleshoot any issues you are having.
  • Make sure to keep your mask and tube clean between uses.
  • Replace masks and tubes every 3 to 6 months with your medical supplier.

What to do if you have an asthma attack while wearing your CPAP

A small 2007 study showed that CPAP machines may actually lower the risk of nighttime asthma attacks. Still, a CPAP machine itself does not treat asthma attacks.

If you have an attack while using your machine, take off the mouthpiece and use your rescue inhaler, at-home nebulizer, or other emergency treatments as prescribed by your doctor.

Speak with your doctor if you think a CPAP machine might help you. This therapy is not used for people who have asthma alone. Instead, doctors recommend it for people who have both asthma and OSA. Since the symptoms overlap, you may have OSA without knowing it.

According to the American Lung Association, symptoms of OSA include:

  • loud snoring
  • choking or gasping for air during sleep
  • intermittent pauses in breath during sleep
  • frequent urination at night
  • dry mouth or headaches upon waking
  • tiredness and trouble concentrating or focusing during the day
  • worsening asthma symptoms

The National Heart, Lung, and Blood Institute says women and those assigned female at birth may experience additional symptoms. These include things like:

  • anxiety
  • depression
  • insomnia
  • frequent waking throughout the night

Symptoms may be tied to hormonal differences, especially in those with polycystic ovary syndrome (PCOS).

Your doctor will consider all your symptoms — as well as your health history and any risk factors — before making a diagnosis. And most doctors will suggest doing a sleep study before prescribing you a CPAP machine.

CPAP machines are not used to treat asthma specifically. Since asthma and OSA can coexist, using CPAP for OSA may extend some benefits to both conditions. Consider making an appointment with your doctor if you have symptoms of OSA, other concerns about your respiratory health, or want to discuss your treatment options.

If you have severe asthma with or without OSA, various new treatments may be worth discussing with your doctor as well.