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Side Effects of Using a CPAP Machine

CPAP therapy has been around for decades, with machines first prescribed to patients in the 1980s. CPAP, which stands for continuous positive airway pressure, is widely used in the treatment of obstructive sleep apnea (OSA), a sleep disorder that causes frequent pauses in breathing due to a brief and intermittent blockage in the airways from muscle relaxation2. The CPAP machine helps keep the patient’s airway open through pressurized air during sleep.

While CPAP therapy is considered highly effective at improving the quality of life3 in people with OSA, patients often complain of uncomfortable side effects. Research suggests that as little as 25 percent4 of patients with mild OSA use their CPAP machines long-term due to discomfort. Let’s look at the common side effects and how you can avoid them to help make your CPAP therapy as effective and comfortable as possible. 

Common Side Effects of CPAP Machines 

  • Aerophagia – Aerophagia is when you swallow too much air5, and this can happen during CPAP use6. When this happens, the pressurized air enters the digestive tract, which can result in uncomfortable bloating, burping, and flatulence. 
  • Claustrophobia – Claustrophobia is a fear of being in enclosed spaces, and it’s a reason why some people discontinue CPAP treatment7. Wearing a mask while sleeping can lead to the fear of feeling trapped or suffocated. 
  • Discomfort – It’s normal to find wearing a mask uncomfortable, especially at first. However, if the mask is ill-fitting, this can make discomfort worse, possibly leading to skin irritation, pressure sores, or air leaks8. Leaking air will result in you not getting the air pressure required to treat your apnea. Some people also find it hard to fall asleep with the feeling of the constant flow of air that’s coming through the mask.
  • Dry Eyes – Air leaks from a poorly fitting CPAP mask can cause air to be directed to your eyes, which can cause them to become dry or teary.8
  • Dry Mouth – A dry mouth is another complaint from CPAP users, and it occurs when air dries out the mouth’s mucous membrane lining9. Mouth breathing is a cause of dry mouth during CPAP therapy because it can dry up saliva. However, nasal breathers who sleep with their mouth open can also experience pressure leaks through the mouth10, which can cause dryness.
  • Dry Nose – The lungs function best with warm, moist air11, and the nasal passages filter, heat up, and humidify the air we breathe. The constant stream of pressurized air delivered by a CPAP machine can disrupt the natural nasal cycle12, resulting in decreased mucus and nasal dryness.
  • Nasal Congestion – Congestion can occur when the air delivered by the CPAP machine is too dry, which can cause inflammation in the nasal passages. Some research13 suggests that patients who already have nasal congestion may be more susceptible to CPAP-induced nasal congestion. A stuffy nose can also indicate illness contracted from a dirty CPAP machine that hasn’t been cleaned properly14
  • Skin Irritations – A mask that’s too tight can lead to sores on the face, while air leaks from a mask that’s not sealed well might cause skin irritation.8 If your mask hasn’t been cleaned properly, you may also experience irritation from the bacteria or oils that have collected on it15. 
  • Sore Throat – CPAP users often wake up with a sore throat if the air delivered is too dry16, which can dry out the throat, leading to inflammation and discomfort. 

How to Prevent CPAP Side Effects 

Despite the potential side effects of CPAP therapy, there are actions you can take to overcome or prevent them. However, if these don’t work, you should always speak to your healthcare provider, who should be able to help you find a solution. 

  • Find the right face mask – Your healthcare provider will likely offer suggestions based on the mask type you need, and you should consider your regular sleep position since some masks are better for side and stomach sleeping than others. You may also find visiting a brick-and-mortar supply store helpful since you can try multiple masks on, but if that’s not possible, some online retailers offer AI mask-fitting technology. Masks typically come with adjustable headgear straps. Make sure the mask strikes a good balance between comfort and snugness. 
  • Clean your mask regularly – Dirty CPAP equipment can lead to skin irritation and sickness, so these items should be cleaned regularly. A strict cleaning schedule17 should involve daily cleaning of the mask and cushioning, and weekly cleansing of the tubing, headgear, humidifier chamber, and reusable filter. Warm, soapy water is generally recommended for cleaning, using a mild, unscented soap.17 Disposable filters should be replaced as per the manufacturer’s instructions, and you should change the distilled water in the humidifier daily.17 Learn more about how
  • Use a nasal spray – If you’re experiencing nasal congestion from your CPAP machine, nasal sprays can reduce blood vessels and tissue swelling in your nose. You can try using a sodium hyaluronate nasal spray18 to ease symptoms.
  • Monitor the pressure – You should never adjust the pressure of your CPAP on your own. Instead, consult your healthcare provider if you feel the pressure is uncomfortable. before attempting to alter the pressure level of the device. Some machines have a “ramp” mode, which delivers air at a lower pressure in the beginning and then slowly builds to the programmed level19. This gradual increase can make it easier for some CPAP users to fall asleep.
  • Consider using a chin strap – Sleeping with your mouth open while using a CPAP can lead to dry mouth because pressurized air can escape through the open mouth and dry up saliva. In this case, try using a CPAP chin strap, which gently keeps the mouth closed while you’re sleeping, or consider switching to a full face mask if you use a nasal mask or nasal pillow mask.8
  • Use a humidifier – If you’re experiencing a dry nose, nasal congestion, or a dry mouth, consider using your machine’s humidifier chamber, or adding an external one if your machine doesn’t have one built in. Heated CPAP tubing can also be used in conjunction with humidifier chambers. Humidifying the air you breathe, especially in cold, dry climates, can help to reduce dryness.
  • Switch to a different therapy or mask type – Research suggests that switching to bilevel positive airway pressure20 (BiPAP) therapy or automatic positive airway pressure (APAP) therapy could reduce aerophagia.6 Additionally, using a nasal mask rather than a full face mask may also reduce aerophagia symptoms as this prevents mouth breathers from swallowing as much pressurized air.

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Using CPAP Accessories to Avoid Side Effects

  • Hoses – You should ensure your hose is properly connected to both the machine and mask to ensure the air is being delivered correctly. Hosing should be long enough to comfortably reach you, and it should be tangle-free to allow for unimpeded airflow. Clean your tubing once a week to reduce the risk of infection. Additionally, heated hoses can further humidify the air from the CPAP, and they can be used instead of, or alongside, a humidifier. These hoses can also prevent condensation from building up in the tube, which can cause you to have a damp face.
  • Filters – Reusable filters should be cleaned, and disposable filters should be replaced according to the manufacturer’s instructions. Failure to do so may cause contamination of the air delivered by the CPAP. A dirty filter can also cause the machine to make a bothersome noise.8
  • Mask liners – Mask liners are an optional accessory that can help make the mask more comfortable by absorbing moisture. Liners can also prevent air leaks by filling any gaps between the mask cushion and your skin, as well as restricting mask movement.
  • Barrier cream – Using regular face cream while wearing your CPAP mask can make the mask slide around or cause the mask cushion to break down. If you’re experiencing skin irritation, the use of a specialized CPAP barrier cream21 can help protect the skin and improve the seal without damaging the mask.

When to Call Your Doctor About CPAP Side Effects

If CPAP side effects impact your life, it’s always best to speak to your physician or sleep specialist. Your healthcare provider may be able to make changes to your treatment plan or explore an alternative to CPAP therapy. Do not discontinue treatment without speaking to your doctor.

Frequently Asked Questions

What are common CPAP side effects?

Common CPAP side effects include general discomfort, dry mouth, dry nose, congestion, skin irritation, bloating, sore throat, and claustrophobia.8 Thankfully, there may be small adjustments you can make that could greatly improve your comfort during CPAP therapy.

Should I be concerned about CPAP side effects?

Most CPAP side effects aren’t considered dangerous, but if they’re affecting your quality of life, then you should speak to your healthcare provider. Discontinuing treatment on your own because of side effects could be dangerous because untreated sleep apnea can lead to serious health complications, including heart failure, high blood pressure, and type 2 diabetes.2

How much does a CPAP machine cost?

The price of CPAP machines varies greatly based on how complex their features are. When purchasing without insurance, you might pay around $500 for a basic machine, and upwards of $1,000 for a more advanced model. Your healthcare provider will discuss the best CPAP machine for you after diagnosis.

What does a CPAP machine do?

A CPAP machine is considered a top treatment for sleep apnea22, which is a condition that impairs breathing while sleeping. The muscles around the throat naturally relax when we sleep, but in some people, this can obstruct the upper airway, leading to lapses in breathing.2 A CPAP machine delivers a continuous flow of pressurized air to the user, which forces their airway open for steady breathing. A CPAP only relieves symptoms of sleep apnea, rather than curing it completely, so it must be used consistently to avoid the dangerous complications of sleep apnea.

Lisa Bowman

Lisa Bowman


About Author

Lisa is a content writer for Sleep Advisor, which combines two of her greatest passions – writing and sleeping. She can also be found writing about fitness, sustainability and vegan food.

Combination Sleeper


  1.  “How the CPAP machine beats deadly sleep apnoea”. The University of Sydney. 2018.
  2. “Obstructive Sleep Apnea”. Cleveland Clinic. Last modified November 15, 2022. 
  3.  Li, Zhiqiang., et al. “Predictors of the Efficacy for Daytime Sleepiness in Patients With Obstructive Sleep Apnea With Continual Positive Airway Pressure Therapy: A Meta-Analysis of Randomized Controlled Trials”. Frontiers in Neurology. 2022.
  4. Qiao, Min., et al. “Long term adherence to continuous positive Airway pressure in mild obstructive sleep apnea”. BMC Pulmonary Medicine. 2023.
  5. Avalos, Danny J. “Aerophagia”. Clinical and Basic Neurogastroenterology and Motility. 2020.
  6. Shirlaw, Teresa., et al. “A Randomized Crossover Trial Comparing Autotitrating and Continuous Positive Airway Pressure in Subjects With Symptoms of Aerophagia: Effects on Compliance and Subjective Symptoms”. Journal of Clinical Sleep Medicine. 2017.
  7. Leggett, Melanie. “A Brief Review of Claustrophobia and Continuous Positive Airway Pressure (CPAP) Therapy for Sleep Apnea”. Journal of Sleep Medicine & Disorders. 2016.
  8. “CPAP machines: Tips for avoiding 10 common problems”. Mayo Clinic. Last modified November 29, 2023. 
  9. Bortolotti MD, Mauro. “The Cause of Dry Mouth During CPAP Application”. Journal of Clinical Sleep Medicine. 2017. 
  10. Pogach MD, Melanie. “I can’t tolerate CPAP, what can I do?” Harvard Health Publishing. 2020.
  11. “Mouth Breathing”. Cleveland Clinic. Last modified April 11, 2022. 
  12. White, David E., et al. “Model identifies causes of nasal drying during pressurised breathing”. Respiratory Physiology & Neurobiology. 2017.
  13. Skirko, Jonathan., et al. “Association of Allergic Rhinitis With Change in Nasal Congestion in New Continuous Positive Airway Pressure Users”. JAMA Otolaryngology – Head & Neck Surgery. 2020.
  14. Godman, Heidi. “Can Your CPAP Make You Sick?” Harvard Health Publishing. 2019.
  15. Helpful Hints for Your CPAP Unit. UNC School of Medicine. Webpage accessed November 23, 2023. 
  16. Soudorn, Chuleekorn., et al. “Effect of Heated Humidification on CPAP Therapy Adherence in Subjects With Obstructive Sleep Apnea With Nasopharyngeal Symptoms”. Respiratory Care. . 2016.
  17. “CPAP Equipment Cleaning and Disinfecting Instructions”. Weill Cornell. Webpage accessed November 1, 2023. 
  18. La Mantia MD, PhD, Ignazio., et al. “Effectiveness of Intranasal Sodium Hyaluronate in Mitigating Adverse Effects of Nasal Continuous Positive Airway Pressure Therapy”. American Journal of Rhinology and Allergy. 2017.
  19. Pinto, Venessa., Sharma, Sandeep. “Continuous Positive Airway Pressure”. StatPearls. Last modified July 24, 2023. 
  20. Pelot, Alain., et al. “Effect of switching from continuous to bilevel positive airway pressure on sleep quality in patients with obstructive sleep apnea: the prospective POP IN VAuto study”. Journal of Thoracic Disease. 2023.
  21. Ghadiri, Maliheh., Grunstein, Ronald R. “Clinical side effects of continuous positive airway pressure in patients with obstructive sleep apnoea”. Respirology. 2020.
  22. “Test your CPAP IQ”. Mayo Clinic Health System. 2022.