Do you really need a humidifier with your CPAP?

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Do you really need a humidifier with your CPAP?

Every CPAP user in Quebec has to deal with it: the need for humidity in our climate.

Even if you’re already using a humidifier, you might have been asking yourself some common questions – like why is a CPAP humidifier important anyway? Does distilled water really make a difference? How do I deal when I travel?

Well, once again Apnea Health has your answers.

Why is a humidifier important? One word: comfort.

By using a heated humidifier, you reduce your chances of waking up with dry mouth in the morning, and being bothered by nasal congestion at night. While in the southern US it’s common to buy just the compressor without a humidifier, here in our Canadian climate, the extra humidity is a must. Because of that, humidifiers are usually included with CPAP machines sold here, so make sure you don’t miss out on their benefits!

Here’s what’s happening with your CPAP. In simple terms, your CPAP draws the ambient air from the room, filters out impurities, then passes it through the tube into your lungs at just the right pressure. It’s like a vacuum in reverse – just less noisy. Now imagine how you’d feel if it were blowing cold, dry air at you all night – ouch!

That’s where heated humidifiers and tubes come in

By using your humidifier, you’ll experience less dryness in your nose, sinuses and lungs. You can also reduce the risk of nasal congestion, inflammation, infections, and nosebleeds.1

As for a heated tube, well, that can help too. With standard tubing you can run into condensation problems – especially if the temperature in your room is on the cooler side. Humidity produced by your CPAP can wind up condensing in the tube if it’s cold, and get stuck there instead of making it to your nose where you want it. You may have noticed some “rainout” in your tube in the morning – which means you’re not getting the benefit of the humidifier and will probably still be stuck with some of the symptoms above.

Resmed ClimateLine Heated Tube for S9 Series

The water level in my humidifier hasn’t budged. Why?

Don’t panic! Your CPAP is working properly.

As we said before, the CPAP takes the air from your bedroom and sends it into your tube. An amazing thing with these machines is they constantly measure the humidity of the air they draw – if it already meets the comfort level you chose for your CPAP, the machine will leave the water tank alone and blow the air as is.

So, depending on the weather, the season, and personal preference, your CPAP’s thirst for distilled water will be different. Most of our patients need less distilled water in the summer, and ramp up in the winter when the air gets drier. Even in summer though, we recommend leaving a little water in your humidifier each night to prevent it from running dry and potentially damaging the heating element over time.

If it feels like your CPAP is causing dryness in your nose, sinuses or lungs, please let us know. We’re all about your sleep comfort. Just give us a call, or drop by anytime we’re open, and one of our respiratory therapists will be happy to help!

What’s with the fancy distilled water?

Lots of patients ask why they can’t just use tap water with their CPAP. After all, we’ve got some of the best tap water in the world – and it’s free – so why not use it?

The reason is there are still microorganisms and minerals in the water from your tap. According to Brandon Peters (2019), a board-certified neurologist and sleep medicine specialist:

“Boiling water will kill microbes, but it will not remove minerals or chemical contaminants. These minerals that make water ‘hard’ include calcium, magnesium, iron, and others—if they are present in the water put in the humidifier’s water chamber, over time scale will develop that discolors the container and could damage the machine. Filtered water may remove some of the minerals but may not remove living organisms or other chemicals. Bottled water that has been distilled is certainly the safest option.’’2

Using distilled water reduces mineral deposits in your water chamber

The odd splash of tap water won’t hurt the tank, but long term, mineral build-up from using hard water will damage the plastic and shorten its life. That’s why most CPAP manufacturers recommend distilled water.

water pouring

What about when I travel?

Travelling’s awesome. It means getting exposed to new cultures, architecture, food, and lifestyles. But it also means getting exposed to some fun new microbes your body isn’t used to. Even if the water’s safe to drink, that doesn’t mean it’s a good idea to put it in your CPAP. Peters mentions that “tap water within Neti pots in Louisiana has led to a few reports of harmful parasite infections affecting the brain. This condition can be fatal and treatment may be ineffective.’’1

All right, that sounds scary, and he goes on to say that “the same risk has not been demonstrated with the use of CPAP,” but think about it – everything in your water chamber gets vapourized and inhaled to your nose, sinuses and lungs. Do you really want to take the risk?

We recommend that you take the time to go buy a bottle of distilled water when you arrive at your destination. Call it a tourist experience – why not? So you get to go check out a grocery store in a new country. Hey, you can even pick up a little of what the locals eat at the same time… you might find it an interesting switch from what’s on the “tourist menu” at the restaurants!

the dreamstation is a great travel buddy

What NOT to do with your water chamber

If you keep in mind that everything that goes in your water chamber can go into your lungs, you should be ok. Wash it every day with mild soap and regular water, rinse carefully, then let it air dry. That’s enough to get rid of any bacteria before you fill it back up with distilled water.

Don’t get any silly ideas about putting alcohol, bleach or ammonia in there, or any perfumes or essential oils to make the air smell pretty – your lungs won’t thank you! Use nothing but soap and water for cleaning, and distilled water for therapy, and everything should be fine.

no bleach

Upgrade to a CPAP with advanced humidification

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Care for Life at Apnea Health

Don’t forget, the Apnea Health team wants to give you the best CPAP care you can get.

All of our patients are made part of our Care for Life Program, so whether it’s helping you tweak the level of humidity in your CPAP, answering any questions you might have, our respirologists and sleep experts are here for you!

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  2. Peters, B. (2019). Do You Have to Use Only Distilled Water in the CPAP Humidifier?. [online] Verywell health. Available at: [Accessed 5 Oct. 2019].