Common Side Effects of CPAP Therapy

Side Effects From CPAP Therapy Are Fixed With Adjustments

Continuous positive airway pressure (CPAP), used to treat obstructive sleep apnea, is relatively safe but does come with a few possible side effects. The most common complaints are about air pressure or discomfort from the mask itself, and these issues can generally be reduced by making adjustments to the settings of your machine or the fit of your mask. 

CPAP is a prescribed therapy with multiple variables to consider, so don't make these changes on your own or you may experience harmful effects.

Apnea Medical Test
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Air Leaking From CPAP Masks

By far, an air leak is the most common complaint associated with CPAP use. If the mask does not fit perfectly, air may escape around the edges, especially as you change position while you are sleeping.

Larger masks, such as those that cover the nose and mouth, are more prone to leaks. Leaks may compromise your therapy by reducing the pressure delivered, or they may be noisy and disturb your bed partner.

Air leaks can be reduced by using a nasal mask or nasal pillows. If you are struggling with the fit of your CPAP mask, altering the pressure settings can sometimes be helpful.

If there is too much air pressure, the excessive air escapes around the edges of the mask or out of the mouth. Discuss this with your healthcare provider before changing the settings.

Skin Marks or Rashes

Your CPAP mask may leave marks on your skin if it doesn't fit properly, possibly leading to sores or even ulcers, especially along the bridge of your nose. People with sensitive skin may also develop a rash or skin irritation, especially with masks that contain latex.

Mask liners, barrier creams, loosening the mask, or a better-fitted mask may relieve these symptoms.

Dryness in the Nose or Mouth

Dryness of your nose or mouth often accompanies leakage. This may lead to nosebleeds or may even damage your gums and teeth. If your mouth falls open, air can escape, leading to a parched mouth or tongue.

If your nose is dry, over-the-counter nasal saline spray can help. Using a heated humidifier and heated tubing can also help keep you from drying out. To keep your mouth from falling open, you can try a chinstrap or a full-face mask that covers both the nose and mouth.

Discomfort Breathing Out

Though it is easy to breathe in, you may find it difficult to breathe out against the pressure when you first start using CPAP therapy. This may improve over time, but the effort may also cause insomnia.

In some cases, ramping from a lower initial pressure or a feature to allow easier exhalation can be helpful. It may be necessary to reduce pressures overall. In rare cases, bi-level therapy—in which one pressure is used to breathe in, and a lower pressure is used to breathe out—may be needed.

Air Swallowing

Many people experience air swallowing, called aerophagia (literally "air eating"). If you wake and your stomach is filled with air, this may be due to aerophagia. 

Symptoms include:

  • Burping
  • Farting
  • Bloating

Air swallowing can be a sign of CPAP pressures that are too high. Rather than entering your upper airway, the excessive air can enter your stomach via your esophagus.

Reduced pressures may help to prevent this. Other treatments for aerophagia include sleeping wedge pillows, medications used for heartburn and gastroesophageal reflux disease (GERD), and bi-level therapy.

Developing Central Sleep Apnea

After using CPAP therapy, some people may start to experience episodes of the breath-holding characteristic of central sleep apnea. You may have complex sleep apnea if central apneas did not account for the majority of your breathing disturbances before starting CPAP but now contribute to more than five events per hour.

This sometimes resolves in time, and it may be alleviated by simply lowering the CPAP pressure. Sometimes, treatment may require a change to adaptive servo-ventilation (ASV) therapy, in which the volume and speed of air can be set to vary according to your needs.

Face Growth Problems in Children

Children who use CPAP should be monitored to avoid developing growth problems of the mid-face related to the pressure of the mask across the nose. Newer mask styles, including nasal pillows, may reduce this risk.


Some people feel confined or enclosed when wearing a mask. This typically resolves over time, particularly if you take the time to adjust gradually to using the mask.

If you have claustrophobia and have trouble wearing your CPAP mask, talk to your healthcare provider about possible treatments for the claustrophobia.

Loud Noise

The noise can interfere with sleep, particularly for the person who you sleep with. While the currently used devices are much quieter than those used in the past, it may take some getting used to. Overall, most partners can adapt more easily to the predictable noise of CPAP than to the noise of snoring, which is very common with obstructive sleep apnea.

Sex Drive

Some people may complain that the use of a CPAP mask is unappealing and could inhibit sex drive for one or both partners. If this is an issue, it is best to have a frank discussion with your partner to decide when you will use it and how to avoid negative feelings about the mask.

Adjusting CPAP Setting

Sometimes, it's necessary to adjust the pressures of the CPAP machine as your risk factors for obstructive sleep apnea change. Several factors can make this necessary, including:

  • Weight changes: Excessive weight is a risk for sleep apnea, but if you lose weight you may start to have problems with air swallowing, mask leak, or difficulty breathing out against the pressure. Lowering your CPAP pressure may help. Weight gain can also require a change in CPAP pressure.
  • Allergies: If you have environmental allergies, optimized treatment with medications or nasal sprays could reduce your pressure requirements by improving airflow through the nasal passage.
  • Surgery: Surgical procedures, including tonsillectomy, nasal septoplasty, and soft palate or tongue surgery, may alter your CPAP therapy requirements.
  • Substance use: If you smoke, snoring and sleep apnea may become more severe. Alcohol use near bedtime can cause muscle relaxation, worsening your obstructive sleep apnea symptoms. If you discontinue the use of any of these substances, your pressure needs may also be reduced.
  • Medications: Medications such as muscle relaxants and benzodiazepines may worsen your symptoms. Discontinuing them may reduce your pressure needs.

Remember that you should have your healthcare provider adjust your settings. It can be dangerous to do it on your own.

A Word From Verywell

Fortunately, changes can often be made to improve the experience with CPAP therapy and to reduce the side effects. If you experience side effects, speak with your sleep specialist or equipment provider, who can suggest solutions for you.

After review of your CPAP data, a determination can be made on how best to change your pressure settings or make other changes.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. American Sleep Association. CPAP vs BIPAP.

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By Brandon Peters, MD
Brandon Peters, MD, is a board-certified neurologist and sleep medicine specialist.