What Are the Side Effects of Using CPAP?

CPAP is the only treatment that is 100% effective for treating obstructive sleep apnea, but a lot of patients struggle with using the device properly and using it every night.

CPAP works by blowing air into the air way to keep the airway from closing at night (this closure is called an apnea, learn more about obstructive sleep apnea here). CPAP therapy consists of a flow generation device, called the PAP machine, or blower, tubing that delivers the air to your airway and a mask that is strapped to your face at night to allow the pressurized air to flow into your airway and your exhalation to come out.

While many people have no difficulty using CPAP and report the best sleep of their lives in the first weeks after they start therapy, this isn’t the case for everyone. In this post we cover the top side effects of PAP therapy (any device- CPAP, APAP or bi-level, read about the difference between these devices here) and how you can reduce or even avoid them.

Irritation on the bridge of the nose caused by the mask and headgear

Image of different types of nasal masksThe mask is the interface between the tubing and your face and when properly fitted it ensures a seal that allows the pressured air into your airway to keep it open and prevent apneas (learn more about different types of masks here).

Making sure that your mask fits properly is the most important thing you can do to ensure comfort and proper usage. This is one of the major benefits of having an in-center titration study and/or a face-to-face CPAP set-up with a credentialed and experienced technician who can help you find the mask that fits your face the best.

Even with a properly fitting mask, because the mask is worn for 8 or more hours per night and the skin on the nose and around the eyes can be thin and sensitive, irritation may affect some patients.

To prevent skin irritation:

  • First make sure the the mask is fitting properly.
  • Check that the straps and cushion are clean and in good condition (learn about how often you should replace these items here).
  • Use a nose pad, bandaid or other soft material like moleskin to help the irritation heal and keep the mask from touching the sensitive area.
  • Prevent future irritation by using lanolin or another lubricant on the area where the mask touches your skin.

Irritation of the eyes from mask leak

Proper mask fitting is very important (read above). With every mask there will still be air leak. The goal is to minimize the air leak and ensure that the air is not causing irritation in your eyes; however, air blowing into the eyes at night can cause dryness and irritation during the day.

In order to not let this stop a patient’s CPAP therapy, opthamologists recommend using thick (gels and ointments, not thinner or less viscous teardrops) artificial tears just before bedtime. It is important to treat both sleep apnea and any resulting eye irritation properly, so you should speak to your doctor.

Irritation of the airways

Especially in dry climates, for older patients or patients taking medications that dry the sinuses, the air ways can get irritated and dry. Nose bleeds (epistaxis) can also happen. Heated humidification will help alleviate this. 

If you’re already using humidification, try these tips:

For a dry nose:

  • Use a saline spray at bedtime. 

For a dry mouth:

  • A chin strap can be used to keep your mouth closed at night if you’re using a nasal mask. You can also consider using a full-face mask which covers your mouth and nose (learn about chin straps and mask types here).


Aerophagia (from the Greek “aerophagein” meaning “to eat air”) is excessive swallowing of air causing abdominal discomfort.

The esophagus is a long tube-like organ that extends from the bottom of the throat to the top of the stomach. The upper essophageal sphinctor (UES) is a band of muscle fiber that contracts or tightens at the top of the esophagus. When you swallow, the UES relaxes to allow food into your esophagus where muscle contractions move the food down to your stomach through the lower esophageal sphinctor (LES) which also relaxes to allow food into the stomach. The LES remains open for 5-8 minutes as food moves down the esophagus and then it closes, to keep food from going back up the esophagus.

Up to 30 ml of air is normally swallowed with food. The stomach swells as the air is ingested and the pressure increases. Once the pressure reaches a certain point in the stomach, the LES reflexively relaxes. This allows the air to escape out of the stomach, up the esophagus, and out of the mouth as a belch.

Image of esophagus

Air can also be swallowed without eating or drinking and is known to affect some CPAP users. It is unclar how much the pressure from CPAP is actually forcing air into the stomach. It may be that some CPAP users complaining of aerophagia have supragastric aerophagia in which air enters the esophagus but does not reach the stomach. It is also possible that CPAP related aerophagia is associated with gastroesophageal reflux disease, aka GERD, a disorder where relaxation of the LES allows gastric fluids to come up from the stomach and into the esophagus.

While there are some drugs and even a surgical option for reducing the pressure that causes aerophagia, some adult CPAP users may be able to relieve CPAP-related aerophagia by:

  • Reducing the pressure by elevating the head or avoiding eating soon before bedtime
  • Avoiding substances such as caffiene and nicotine that induce relaxation of the lower esophageal sphincter
  • Reducing the pressure in the airway by using the lowest treating CPAP pressure. An auto-titrating PAP or APAP may help with that (learn more about different PAP devices here).
  • Consider using a bi-level PAP. The lower expiratory pressure may reduce the amount of air that gets into the stomach.

Claustrophobia or sensation of suffocation

Clautrophobia and anxiety about wearing a CPAP mask all night are common among poeple first starting CPAP therapy. Studies have shown that having sleep apnea releases hormones that can cause anxiety and panic. Additionally, a person who suffers anxiety in general may have more anxiety about medical equipment and procedures and may be more likely to have a panic attack at night when trying to fall asleep. 

If you know that you suffer from claustrophobia, anxiety or panic attacks, tell your sleep study or CPAP set-up technician.

There are several steps you can follow to relieve your anxiety:

  • Select the mask that makes you feel most comfortable. For some people it’s the least invasive nasal pillows mask that makes them feel less restricted because it interferes with your field of vision the least. If you’re a mouth breather, you may prefer a full-face mask to a nasal mask with chinstrap so that you can open your mouth if you need to. If possible, have a mask fitting with a technician who can assure the best mask for your face and comfort.
  • Get to know your mask. It has exhalation ports for the air that you are breathing out. They also allow room air to come in, if needed (so there’s no way you can really suffocate). It’s actually a very sophisticated device.
  • Try wearing the mask for a few hours while watching TV, reading or knitting. Slowly become more comfortable with the mask and device.
  • Try breathing exercises to relax you before going to bed and as you fall asleep.
  • Talk to your CPAP provider or your physician about CPAP desensitization or acclimitization. You can work together to determine a timeline for building up your usage of the machine over the first few weeks.

Difficulty exhaling

Some people experience difficulty exhaling against the pressurized air from their CPAP.

There are several options for reducing this:

  • The latest CPAP devices help with this by allowing a timed ramp up feature which slowly increases the pressure while you are first using the machine at night and falling asleep. The device then works at its set pressure while you are sleeping.
  • Another feature of the devices that we use is expiratory pressure relief that slightly lowers the pressure when you are breathing out so that breathing feels smoother and more natural.
  • Try using an autoset PAP device so that the pressure only increases when you need it. An autoset device is set to adjust to a minimum and maximum pressure based on your breathing each night- it only increases when you need it (like when you’re sleeping on your back or have had an extra drink before going to sleep).
  • Try using a bi-level PAP device which has a lower pressure when you breathe out. These devices are more expensive than a regular CPAP (continuous pressure) or autoset PAP device. It may be covered by your insurance if you had a sleep study and demonstrated that you cannot tolerate CPAP.


Insomnia may be a side effect of sleeping with CPAP, but it is also a common symptom of sleep apnea. With sleep apnea, you are waking up dozens of times per night (or even per hour) and this disruption to your sleep may cause insomnia.

Keep in mind:

  • You may find that your insomnia goes away once you use CPAP and your sleep cycles regulate.
  • If the insomnia doesn’t go away, take a look at your sleep hygiene. What is your routine around bedtime? Are you going to bed and waking up at the same time each night. Learn more here.
  • Finally, some patients need sleep aids to help them get through the first weeks of therapy. Talk to your doctor about this.

If you’ve recently started CPAP therapy and are struggle with any of these effects, you should speak with your doctor or CPAP provider. If we provided you’re device, we are here to help! Request an appointment to meet with our technicians or email us at papsuccess@sleepdr.com.

Request CPAP appt.

Dr. Said Mostafavi


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  1. J Reply


    • Julia Rodriguez Reply

      Ha! Yes. Also: energy, focus, sex-drive… the list goes on.

  2. Brian Reply

    I’m wearing the dull mask all might and it’s working for me but since I started wearing it I’ve been waking up with a stiff neck is this common if so van it be avoided

  3. Rene Naranjo Reply

    I have been experiencing muscle aches and tightness in the joints when using the CPAP when I stop using the CPAP these experiences go away..

  4. Cindy Shanks Reply

    I have never had allergies before using a CPAP. Since I started using a CPAP in January most mornings after about a half hour of getting up l sneeze and sneeze blow my nose every 2 minutes and right eye tears. This last from 4 to 8 hrs. I cannot figure what is making me do this allergy pills don’t seam to work.

    • Larry Furrer Reply

      I have exactly the same issues. Sometimes I don’t use it for a couple days and I don’t have them. Has anyone responded to you with any kind of solution to this?
      Larry Furrer

  5. Srivari Reply

    Wonderful Blog

  6. d brooks Reply

    The cpap has made my nose miserable/ getting up at least twice in the middle of the night, , because my nose
    is so stuffy I cant breathe, and takes almost an hour to clear each time and my nose can get stuffy 3 to 4 times a day .I can’t say it has given me a healthier night’s sleep. I now have to use spay’s, a warm cloth, steam, and whatever works to clear my nose

  7. Jenn Brake Reply

    I do not have an allergy or a cold. I breath clearly all day. When I wear my mask I get nasal congestion immediately. It lasts all night as long as I have the mask on. Ultimately, I wake up at some point and I find that I have removed it. I’m only getting between 4-5 hours of sleep with the mask on and I typically end up sleeping for about 7-8 hours. It is very uncomfortable and it feels like it is defeating the purpose, like I am being smothered. I’ve tried different masks and they fit well. I’ve tried the full face mask but I’m now just using a nasal mask. It makes no difference what type of mask I use. Every night is a struggle and I even wear it for a time prior to sleep. As soon as I take off the mask a few minutes pass and the congestion subsides. I sleep propped up on pillows as well. Any suggestions you have would be appreciated. Thank you.

  8. Sylvia Flowers Reply

    I been having throat infections and tonsils since Istarted using the cpap machine. NEVER had this problem before.

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