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Aerophagia Causes and Resolutions


CPAP users who experience excessive belching, stomach bloating, stomach distension and agonizing gas pains may be suffering from aerophagia. It’s the medical term for the phenomenon when air enters the esophagus, goes into the belly and causes bloating.


Aerophagia can be caused by eating, drinking or even talking too fast. It can occur with hyperventilation from anxiety, from chewing gum, smoking cigarettes and even during strenuous exercising.

For the CPAP patient, aerophagia and stomach bloating is much more prevalent than you might think. It’s not a subject many feel comfortable talking about, but this side effect of CPAP use is an important issue to discuss and with proper changes to therapy, it can be resolved.

Aerophagia occurs when air from a CPAP enters the esophagus and goes into the belly, rather than the airway and into the lungs. This can cause gas pains and distension of the stomach. It is common and can happen to anyone who uses CPAP. But when it becomes chronic, it’s a red flag, a symptom that can be overcome when the cause is properly determined.

There are many possible causes; the following are provided:

  1. Your CPAP pressure may be higher than you require. The extra air has nowhere else to go – thus, it is directed in to the esophagus and on to the belly.

  2. Your pressure may be too low and inadequate to resolve your apnea event. In your effort to get more air into your lungs, you gulp air in quickly and it is forced into the esophagus instead.

  3. You may have nasal congestion from a cold, flu or allergies. When your nose is stuffy, you may not be able to receive the CPAP air pressure you need, so you gulp air by mouth and down into the esophagus it goes.

  4. You may be a mouth breather, who is wearing a traditional nasal mask. As your mouth falls open during sleep, the air that is delivered by CPAP and intended to enter the lungs may instead, escape via your mouth. Your apnea events are not being resolved and in your unconscious panic to breathe, you may suddenly have a choking sensation and gulp air in quickly, forcing it into the esophagus.

  5. You may be having difficulty learning and adjusting to exhale over the constant pressure of the air delivered by CPAP. This is especially difficult for those patients on mid- to high-CPAP pressures. Inhalation of high pressures may be easy, but exhaling may cause anxiety, panic and a feeling of suffocation or choking. When this occurs, the patient may fall out of the natural rhythm of breathing and hyperventilation may occur. This can result in a quick sucking in or gulping of air, and that air may be forced into the esophagus rather than the lungs.

Here are a few suggestions:

  1. If you suspect your CPAP machine air pressure might be inadequate for reasons mentioned above (too high or too low), discuss a pressure change with your doctor.

  2. Confirm with your CPAP provider that your machine was indeed set correctly as prescribed by your doctor. On occasion, mistakes happen and CPAP may be set incorrectly.

  3. Expiratory pressure relief features are available on most CPAP machines today. Depending on machine brand, it may be called CFLEX, AFLEX OR BIFLEX on Philips Respironics brands and EPR (expiratory pressure relief) on ResMed brands. This feature automatically reduces air pressure upon exhalation and can help reduce or eliminate aerophagia. Contact your CPAP provider and inquire if this feature is enabled and set on your machine. This is commonly a patient controlled feature, so ask to be shown how to use it.

  4. Consider if the mask you are using is the best choice. You may be a mouth breather yet using a nasal mask. Your mask may not be the best size or style suited for your face. If you experience frequent mask leak, or pressure point soreness from over tightening straps to eliminate leak, consider choosing a different mask.

  5. Make sure you know how to properly fit and adjust your mask for best seal. After you have chosen the best mask size and style for your face, you must adjust it properly before sleep. Sit on your bed, turn the machine on, and place mask on your face with straps loose. Lay down in your sleeping position with your head on your pillow as you would normally sleep. Slowly pull the straps JUST UNTIL you get a good seal. If your mask has a dual cushion, it will need to be “seated.” After you have fitted and adjusted your mask using the steps above, to “seat,” gently pull the mask straight out and away from your face to allow the dual cushions to inflate properly. Lay the mask gently back onto your face . You should know, by feel, that a good comfortable seal is achieved.

  6. If you suspect your aerophagia is the result of hyperventilation caused from anxiety, consider utilizing Cognitive Behavioral Therapy provided by a sleep specialist. Ask your sleep doctor for a referral.

Learning the cause of aerophagia is key to resolving it. As always, discuss this issue with your sleep doctor and CPAP provider to help determine your causes and resolutions.

Can a CPAP machine cause Bloating

This is my issue. I have a pressure of 18cm of water. My Cpap ResMed fills my intestines up. In the morning I wake up with abdominal pain and cannot straighten fully until I have expelled the air by extended periods of farting. I quit using the Cpap machine because of this. I was surprised that no one at Mission Sleep Center here in Asheville, NC explained that this might be a possibility during my Sleep Study introduction and overnight’s. I just woke up one morning after the first three days and could not get out of bed due to the pain in my abdomen. After several mornings of this I said to hell with that.
Four years later I have returned to the Sleep Center. I’ve heard there have been new developments with the machines. I was required to undertake another Sleep Study - not inexpensive. Bipap didn’t work.
Not until I read this entry just now (February 2017) have I ever heard anything about CFLEX, AFLEX, BIFLEX, or EPR.
I’m scheduled to take my latest test results to Advance Home Care this week. I wonder is they’ve even heard of the word: “aerophagia.” …thank you.


Hi Patt. If you would like to email me your contact information, I would be happy to communicate with you privately. My email is:

Hang in there!!


Thank you!
I will be sure to do that.