CPAP Side Effects and the Usual Fixes
This page is general information. It is not medical advice. Talk to your clinician about your own health. If you have chest pain, signs of a stroke or severe trouble breathing, call 911 or go to an emergency room.
The most common CPAP side effects are a stuffy or runny nose, dry mouth, nosebleeds and sore skin where the mask sits. NHLBI and Cleveland Clinic both list these. Most of them come from dry air or a mask that does not fit, and both can usually be changed. Bloating or stomach pain is different. NHLBI says to stop and call your provider right away.
At a glance.
- Nose and mouth dryness often eases with a heated humidifier.
- Red marks and leaks usually mean the mask size or style needs to change.
- Stomach discomfort or bloating means stop and call your provider.
- Getting used to CPAP takes time. Tell your care team early instead of quitting.
Why CPAP Causes Side Effects at All
A CPAP machine pushes a steady stream of air through a hose and a mask. NHLBI explains that the mild air pressure keeps your airway open while you sleep. That is the whole point. But moving air all night dries things out, and a mask strapped to your face for hours can rub. Those two facts explain most of the list below.
Stuffy Nose, Runny Nose and Nosebleeds
Cleveland Clinic says congestion, a runny nose and nosebleeds are often caused by cold, dry air, and that a heated humidifier can often help. Many machines have a water chamber built in. NHLBI says your provider can help you use the humidifier and adjust the settings.
If your nose stays blocked, tell your clinician. A blocked nose can push you to breathe through your mouth, which leads to the next problem.
Dry Mouth
Dry mouth is on both the NHLBI and Cleveland Clinic lists. It often shows up when air escapes through an open mouth. The humidifier helps here too. Some people do better with a mask that covers the nose and the mouth. NHLBI notes that masks can fit over the nose alone or over the nose and mouth, and says your provider will work with you to find the one that fits best.
Sore Skin, Red Marks and Leaks
Cleveland Clinic lists skin irritation and redness from the mask, and says the right size mask and padding can reduce it. A strap pulled very tight is a common cause. People often tighten the mask to stop a leak, and the skin pays for it. A better fitting mask usually fixes the leak and the soreness together.
Bring the mask to your follow up visit or to your equipment supplier and show them where it hurts. Sizes and styles vary a lot, and switching is normal.
Stomach Discomfort or Bloating
This one is not a comfort issue. NHLBI says that if you have stomach discomfort or bloating, you should stop using your CPAP machine and call your healthcare provider right away. Your provider may need to change your settings. Do not try to fix the pressure yourself.
Feeling Closed In or Unable to Fall Asleep
Some people feel trapped by the mask, or find the air pressure hard to fall asleep against. NHLBI says getting used to CPAP can take time and patience. The Sleep Foundation suggests wearing the mask for short practice sessions while you are awake, like while reading or watching TV, so your body learns it is safe.
Many machines also have a ramp setting. The Sleep Foundation describes it as starting at low pressure and rising slowly to your prescribed level as you fall asleep. Ask your care team if your machine has one and whether you should use it.
Keeping the Equipment Clean
NHLBI says to clean your mask and tube every day and to refill your prescription on time so the mask and tube get replaced. Cleveland Clinic also says you will need to see your provider to renew the prescription for a new mask and tube now and then. Old cushions lose their seal, which brings back the leaks and the sore spots.
What Not to Do
- Do not quietly stop. Cleveland Clinic says CPAP only works if you use it every time you sleep. If it is not working for you, say so. There may be other options, and our guide to CPAP alternatives covers them.
- Do not change the pressure yourself. Settings come from your prescription.
- Do not ignore bloating or stomach pain. Stop and call.
If you have Medicare, using the machine also matters for coverage. Our post on the CPAP 4 hour rule explains why.
Who to Call
Start with whoever prescribed your machine. For mask fit, your equipment supplier can often help the same week. If you no longer have a sleep clinician, our directory lists sleep apnea providers by state and city. A listing is not a referral, and we do not give medical advice.
Common Questions
What is the downside of using a CPAP machine?
The usual downsides are a stuffy or runny nose, dry mouth, nosebleeds and sore skin from the mask. NHLBI and Cleveland Clinic list these. Most can be eased with a humidifier or a better fitting mask. Stomach discomfort or bloating is a reason to stop and call your provider right away.
Why do I wake up with a dry mouth on CPAP?
Often air is leaking out through your mouth, or the air is too dry. A heated humidifier or a mask that covers the nose and mouth may help. Ask your provider or supplier to check your setup.
Can CPAP make my stomach bloated?
It can happen. NHLBI says to stop using the machine and call your healthcare provider right away if you have stomach discomfort or bloating.
How long does it take to get used to CPAP?
It is different for everyone. NHLBI says it can take time and patience. Short practice sessions while awake and help with mask fit often make it easier. Tell your care team early if you are struggling.
Keep Reading
- CPAP alternatives
- The CPAP 4 hour rule
- Sleep apnea treatment options explained
- Find a provider with our lookup
- Sleep apnea providers in Indiana
- Sleep apnea providers in Michigan
Sources
- NHLBI, CPAP
- NHLBI, Sleep Apnea Treatment
- Cleveland Clinic, CPAP Machine
- Sleep Foundation, How to Get Used to CPAP
NightWells publishes information, not medical advice. Nothing here replaces being seen by a clinician who can examine you.
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