CPAP dry mouth: What causes it & ways to stop it

Man using a CPAP mask and device in bed, whilst reading a book.

Last updated on January 31st, 2023 at 12:29 pm

Is it normal to have a dry mouth using CPAP?

Are you waking up in the morning with a dry mouth, throat or nose? If so, then this is a common side effect of CPAP therapy (Continuous Positive Airway Pressure).

You might wonder what causes a Sleep Apnoea dry mouth while using a CPAP machine. This page will help you understand what causes dryness and simple ways to stop it.

Why does my CPAP dry out my throat?

If you use a CPAP machine, you might find that the air pressure flow is too high, causing you to have a dry mouth.

It can be hard to stick to using your CPAP device when you find it uncomfortable and suffer from a dry mouth and throat. According to the Oral Cancer Foundation, 30% of all cavities in older adults are caused by dry mouth.

So, how does CPAP therapy cause a dry mouth?

  • Mouth Breathing – There are two types of CPAP masks, nasal masks (which cover just the nose) and full-face masks (which cover the nose and mouth). Those that use a nasal mask and open their mouth during the night may wake up with a dry mouth as their mouth falls open.
  • Mask Air Leaks – Another reason you could suffer from a dry mouth is that your mask does not fit correctly. If your mask is too big or too small, mask leaks occur. The air leaking out can dry out your mouth or nasal passages. If you use a CPAP humidifier and suffer from dryness, this could be because your mask is leaking or the air pressure is incorrect. When your mask seal is not secure dry air from the room can leak into your mask while the warm air escapes.
  • Decreased Saliva Flow – Saliva flow can be reduced by the high pressure of your machine; this usually keeps your mouth moist. Without this, a dry mouth, throat and nose occurs.

There are other reasons you may suffer from a dry mouth that does not relate to CPAP therapy. It is helpful to rule these out before making any changes to your therapy:

  • Medications – Different medications can commonly cause a dry mouth, for example, antidepressants, sedatives and decongestants (if you use any medications, please check if dry mouth is a symptom or side effect). 
  • Dehydration – Dehydration is formed when there is insufficient fluid in the body. Age can impact the development of dehydration, as our sense of thirst can decrease when we age. 

How do you get rid of dry mouth from CPAP?

Fortunately, there are ways to stop dryness caused by your CPAP machine. Over 40% of CPAP users struggle with a dry mouth; here’s how to relieve yourself of the problem: 

Use a CPAP Humidifier

The cold and dry air from your machine can cause a dry mouth, chapped lips and dry nasal passages. 

When you breathe without a CPAP machine, your nose works as a natural humidifier, using your body temperature to warm up the air inhaled. The air your device provides reaches your upper airways before your nose has time to warm it naturally.

CPAP humidifier works by warming up the air you breathe from your machine, removing the risk of a dryness. 

If you intend to travel, you could consider taking waterless-disposable humidifier, which lasts up to 24 hours.

If you already use a humidifier, increasing your humidity levels in the settings can help to prevent dryness.

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Find the most suitable CPAP mask

If you’re finding your mask does not fit correctly and you’re suffering from mask leaks you could try a different size or type of CPAP mask.

Most CPAP machines will give you mask leak alerts to help you troubleshoot this issue. Check your device data for any information on mask leaks. For example, ResMed’s AirSense 10 offers the myAir app to help you track and manage your sleep data.

If you breathe through your mouth at night or sleep with your mouth open switching from a nasal mask to a full-face mask could also significantly improve your comfort and leak rate.

To make your mask and equipment last its lifespan cleaning your CPAP equipment is essential.

It is helpful to remember that you will need to replace your CPAP mask every 6-9 months. The condition of your mask parts can cause mask leaks. Replace mask/mask parts if it shows any wear or tear or if you feel the mask is not working as efficiently as when you first purchased it.

Here at Intus Healthcare, we have a 90-day warranty on our CPAP masks.

Stay hydrated

Although dehydration may not be the cause of your dry mouth, it can make it worse.

Aim to drink eight 8-ounce glasses of water daily; rehydrating will benefit your CPAP therapy. Staying hydrated helps prevent colds, congestion and sore throat.

Use a CPAP chin strap

A nasal mask should only be used when you breathe through your nose at night. However, if your mouth drops open, a chin strap will prevent it. A chin strap holds your mouth closed to stop air from escaping, which causes a dry mouth, nose and throat.

Relieve nasal congestion

Using a nasal irrigator will help you avoid breathing through your mouth.

The SinuPulse Elite Nasal Irrigator is a fast and effective way to cure nasal and sinus congestion. The simple device cleanses sinuses to prevent colds, congestion, blocked noses and sinusitis with a clinically proven saline solution.

For more tips on relieving congestion take a look at our sinus and nasal care products or our nasal irrigation advice.

Use CPAP heated tubing 

If you already use a humidifier with your CPAP device, adding heated tubing will benefit your CPAP therapy.

Heated tubing prevents ‘rainout’ from occurring in your mask. This is when the warm arm made by your humidifier cools and causes condensation. 

Using heated tubing ensures you’re supplied with the full benefit of humidified air as it prevents the cool-down process from the CPAP machine, through the tube and into the mask.

Alternatively, you could use a hose fleece to warm your therapy.

Need more tips?

If you need further advice, please contact us to speak to one of our friendly team.

Helpful articles:

Should I use my humidifier in the summer?

Should you use distilled water in your CPAP humidifier?

Choosing a CPAP mask

How to be comfortable with your CPAP mask

CPAP Mask Leaks: Simple Solutions

Author Danielle Myatt