8 Common CPAP Side Effects

Side Effects From CPAP Therapy Are Fixed With Adjustments

If you use a CPAP (continuous positive airway pressure) machine or are interested in getting one, you might be wondering about possible side effects. CPAP machine side effects include skin marks, dry nose and mouth, and bloating due to air swallowing. These and other effects usually stem from the air pressure being pushed out or discomfort from the mask itself.

Side effects of this treatment can generally be reduced by making adjustments to CPAP machine settings or the fit of your mask. However, CPAP is a prescribed therapy with multiple variables to consider, so it's important that any such changes are made with your healthcare provider's OK.

This article looks at some of the most common side effects of CPAP and how they can be managed.

Apnea Medical Test
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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 and barrier creams can help, as can loosening the mask or using a new mask that fits better.

Nose or Mouth Dryness

Dryness of your nose or mouth is often due to air leaking out of the mask—a very common complaint. This can happen if the mask does not fit perfectly, especially as you change positions while you are sleeping, or if the air pressure is too high.

Nosebleeds or even damage to your gums and teeth can occur due to the dryness. 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.

Note, however, that larger masks—such as those that cover the nose and mouth—are more prone to leaks.

Reducing Air Leaks

Air leaks can be reduced by using a nasal mask or nasal pillows, or by lowering the air pressure on your CPAP machine. Never change the settings on your CPAP without discussing it with your healthcare provider so you ensure you are still getting adequate treatment.

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.

Swallowing Air

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

Symptoms include:

  • Burping
  • Farting
  • Bloating

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

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

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.

Claustrophobia

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 your fear and anxiety.

Loud Noise

The noise a CPAP machine makes can interfere with sleep, particularly for the person who you sleep with. While today's 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.

Factors That Impact CPAP Side Effects

Many CPAP machine side effects occur when people don't use the machine in a way that's optimal for them. For instance, side effects can occur when:

  • Your mask doesn't fit properly.
  • You're not using the built-in heated humidifier.
  • Your mask doesn't cover both the nose and mouth.
  • Pressures are too high.

Sometimes, certain factors increase your risk of experiencing side effects and signal that you may need to make adjustments to your CPAP machine. These factors include:

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, 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.

Preventing CPAP Side Effects

Adjusting your CPAP machine and taking certain precautions can help ward off CPAP machine side effects:

  • Make sure your mask fits well.
  • Use a mask liner or apply a barrier cream.
  • Use a heated humidifier or heated tubing.
  • Use a mask that covers both the nose and mouth.
  • Transition slowly from a lower initial pressure to a higher pressure.
  • Lower your machine's pressure in general.
  • Have your child use a nasal pillow.
  • Talk to a healthcare provider about your fears and anxieties.

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

Summary

CPAP therapy can have a number of side effects. The most common ones relate to air mask leakage, but other side effects may include skin rash, bloating, and discomfort breathing out. Certain factors can impact whether or not you experience side effects, such as how well your mask fits and the machine's air pressure level. Losing or gaining weight, taking certain medications, and other variables may also influence CPAP machine side effects.

Most side effects can be corrected by adjusting the machine's settings and making sure your mask fits correctly.

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