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CPAP Side Effects and What to Do About Each One

Getting Started
September 20, 2026
8 min read
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Nobody warns you about the bloating. Or the nose that runs all morning. Or waking with a mouth so dry your tongue sticks to your teeth.

I almost gave up on CPAP in my first month. Looking back, none of what I was fighting was unusual, and almost all of it has a fix. What I lacked was somebody to tell me that.

So here is the list. Each side effect, why it happens, and what usually sorts it out. None of this replaces your doctor, but most of it you can raise with your supplier this week.

Dry mouth and a dry throat

The most common complaint of all, and usually the easiest to solve.

It happens because your mouth falls open while you sleep. Air takes the shortest way out, straight past your tongue, drying everything on the way.

What usually works:

  • Turn the humidifier up a setting or two, and do it gradually.
  • Try a chin strap, which holds your jaw closed while you sleep.
  • Ask about switching to a full face mask, which covers your mouth as well as your nose.
  • Use heated tubing if your machine takes it, which stops the moist air cooling on the way.

If your mouth is dry and your machine reports high leak numbers, the mask is probably the cause rather than the humidifier.

A blocked or runny nose

Very common in the first weeks, and often mistaken for a cold that will not go.

Pressurized air irritates the lining of your nose. Your nose responds the way it responds to any irritation, by producing more mucus and swelling slightly.

What usually works:

  • Raise the humidity, since dry air makes it worse rather than better.
  • Warm the air using heated tubing if you have it.
  • Rinse with a saline spray or a nasal rinse before bed.
  • Ask your doctor about a steroid nasal spray if it persists past a few weeks.

Most people find this settles on its own within a month. If it does not, say so rather than waiting it out.

Bloating, burping, and trapped wind

This one has a name, aerophagia, which simply means swallowing air. It is far more common than people admit, because it is not a comfortable thing to bring up.

Air that should go into your lungs goes into your stomach instead. You wake up bloated, gassy, and uncomfortable.

What usually works:

  • Ask about lowering your pressure, or about a machine setting that eases the pressure as you breathe out.
  • Sleep on your side rather than your back.
  • Raise the head of the bed slightly.
  • Ask whether an APAP or BiPAP would suit you better, since both can lower the pressure you fight against.

Do not adjust your own pressure. That setting comes from your sleep study, and changing it yourself can undo the treatment.

Sore skin, red marks, and pressure sores

If you wake with deep marks that are still there an hour later, your mask is too tight or the wrong size.

The instinct is to pull the straps tighter to stop a leak. It is the wrong instinct, and it causes most of the skin problems people blame on the mask itself.

What usually works:

  • Loosen the straps, then tighten only until the leak stops.
  • Get fitted in person rather than guessing the size.
  • Try mask liners, which put soft fabric between silicone and skin.
  • Replace the cushion, since worn silicone grips instead of sealing.

Broken skin needs a doctor rather than a workaround. Do not sleep through it hoping it heals.

Dry, sore, or watery eyes

This is nearly always a leak pointing upwards. Air escapes from the top of the mask and blows across your eyes all night.

You may sleep through the leak itself and only notice the eyes in the morning.

What usually works:

  • Refit the mask lying down, in your actual sleeping position.
  • Replace the cushion if it feels tacky or has lost its shape.
  • Ask for a different mask style if it keeps happening.

Feeling boxed in

Claustrophobia is real, and it stops more people than any mechanical problem does. It is not weakness and it is not permanent.

What usually works:

  • Wear the mask for short spells while awake, watching television, with the machine off.
  • Then wear it awake with the machine on, to get used to the pressure.
  • Then use it for naps before you use it all night.
  • Ask about nasal pillows, which are the smallest option and sit inside the nostrils.

Build up over a week or two. Most people who do this stop noticing the mask entirely.

Noise, yours or theirs

A modern machine is quiet. If yours is loud, something is wrong rather than normal.

Check the filter first, because a clogged one makes the motor work harder. Then check for a leak, since most of the noise people complain about is escaping air rather than the machine.

If your partner is the one losing sleep, a longer hose helps, and so does moving the machine off the bedside table onto something soft.

When to stop troubleshooting and call

Call your supplier this week if any of these are true:

  • You have tried the fixes above and nothing changed
  • Your skin is broken or blistered
  • You are still exhausted after several weeks of proper use
  • You have chest pain or shortness of breath, which needs your doctor rather than your supplier

A good supplier expects these calls. Handling them is the job. If yours will not help, that is a reason to look at another one.

Your next step

Pick the one side effect bothering you most and try the first fix on its list tonight. Just one, so you know what worked.

If it is still there in a week, call your supplier and describe it plainly. Say what you tried and what happened.

If you need a supplier who actually answers, find one near you on CPAPLocator.

*CPAPLocator.com is a directory service only. We are not a medical provider. Content is for informational purposes only. Always consult your healthcare provider.*

Frequently Asked Questions

Why does CPAP make me so bloated?

You are swallowing air, which is called aerophagia. It usually means the pressure is higher than you need, or that you are sleeping on your back. Ask your supplier about a pressure review rather than adjusting it yourself.

Why is my mouth so dry with CPAP?

Your mouth is falling open at night, so the air escapes through it and dries everything out. A chin strap, more humidity, or a full face mask are the usual fixes.

Is a blocked nose from CPAP permanent?

Rarely. It is your nose reacting to pressurized air, and it usually settles within a few weeks. More humidity helps. If it lasts longer, ask your doctor about a nasal spray.

How do I stop CPAP leaving marks on my face?

Loosen the straps until you hear a small leak, then tighten only until it stops. Marks usually mean the mask is too tight or the wrong size, not that you need to pull harder.

Can I adjust my own CPAP pressure?

No. Your pressure comes from your sleep study and is set for your airway. Ask your supplier or doctor to review it instead.

What if I feel claustrophobic wearing the mask?

Build up to it. Wear it awake with the machine off, then awake with it on, then for naps, then overnight. Nasal pillows are the smallest option if a full mask feels like too much.

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