Why You Should Use Distilled Water In Your CPAP

People who use a continuous positive airway pressure (CPAP) machine to treat sleep apnea usually have a CPAP humidifier to prevent dryness, especially in the nose and sinuses. This may reduce the risks of infection, inflammation, nosebleeds, and nasal congestion.

This device works by delivering a flow of pressurized air through a mask to keep airways open and prevent apnea episodes (when breathing stops). The instructions typically say you should use distilled water in the humidifier, but people often wonder about other options.

This article explains why you should use distilled water in your CPAP machine. It answers questions about whether you can use boiled water, bottled water, or make your own distilled water if none is available.

Can You Use Tap Water With a CPAP Humidifier?

Minerals like calcium, magnesium, and iron are what make your tap water "hard." Filtering can remove some of the minerals. It may not remove microbes or other chemicals, though. Boiling will remove the germs, but then it doesn't remove minerals or chemical contaminants.

In addition to health concerns, using tap water with mineral content could damage your CPAP machine with a buildup of scale due to the minerals.

Distilled water prevents mineral deposits, and most manufacturers recommend its use. However, it is possible to use tap water without significant risk. You will have to work harder to clean the machine and prevent excess mineral buildup in the tub.

It's fine to occasionally use tap water to clean your CPAP machine.

What About Other Types of Bottled Water?

Bottled water can be an option for people using a CPAP machine who don't have access to the recommended distilled products.

A British study of 251 people who traveled with a CPAP machine found that, for the humidifier, it was safe for them to use tap water and other clean water sources including:

• Bottled water
• Filtered water
• Boiled water that was then cooled
  

In most cases, however, CPAP machine manufacturers and water providers do not recommend the use of mineral water, spring water, tap water, and other sources that affect machine performance. You'll want to check with the company or your healthcare provider if you have questions.

What You Shouldn't Put in Your CPAP Humidifier

Remember that you are exposing your lungs to the water you put in the humidifier, and some substances can make you ill. In one case, a person added hydrogen peroxide to their humidifier to protect against the COVID-19 virus and developed chemical pneumonitis from the airway injury.

The health risks also are a good reason to clean your CPAP machine regularly. When cleaning your humidifier, don't use:

• Bleach
• Alcohol
• Chlorine
• Ammonia
• Moisturizing, glycerine-based, and antibacterial soaps

These substances could damage your lungs. Avoid using water softeners and descaling agents in the water tub, and do not add substances to the water that include perfumes, colognes, or scented oils, either.

Tips for Traveling

Many people travel easily with a portable CPAP machine, even on long air flights. Very few people report problems with check-in or other factors, although some required documentation.

Water is just one concern for CPAP users when traveling, and researchers offer some tips. One study described:

• Power cord, battery, and adapter issues (make sure you have the right type and/or length)
• Filter concerns (you may need more in a dusty climate or location)
• Challenges with machine size (the smaller the better)

Consider local water safety as well. Distilled water is always preferred and options are acceptable, but if you're in an area with poor water quality, you can be exposed to harmful substances.

What if Distilled Water Isn’t Available?

With CPAP and distilled water, there are a few options if you don't have access. But first check grocery stores, or even specialty or hardware stores.

Make Your Own

Distilled water is boiled water that is collected after it becomes steam. You can do this on the stove at home but you need to place a smaller, heatproof container inside the larger pot of boiling water. With the lid placed upside down, it will cause the steam to collect in the smaller second pot.

Placing ice in the lid will help the steam condensation process to go faster. Keep in mind that distilling water removes all impurities for CPAP use but it isn't ideal for cooking.

Boil Water

You can boil water without distilling it, but remember that it doesn't remove minerals or chemical contaminants. While it does remove germs and some experts find it safe, it's not ideal.

You shouldn't used boiled water for more than a day or two until you can access distilled water.

Don’t Use Water

If you don't want to take the risk, you can use a CPAP machine without the humidifier element, and therefore, without water. The machine will continue to work and will simply use dry air. Just remember to turn off the humidifier unit.

The airway tissues in your nose and mouth may become extremely dry, though. The dry air can increase the risk of infection and inflammation. An over-the-counter nasal saline spray can help with symptoms until you can return to using humidified air.

Summary

Using the humidifier in your CPAP machine can help prevent problems in your nose and sinuses.

Tap water may be safe to use in your CPAP humidifier, but the safest option is distilled water. Tap water sometimes contains minerals that will build up inside your machine. It may also contain dangerous microbes and chemicals.

Avoid adding things like perfumes or scented oils to your humidifier water. Avoid harsh cleaning agents when cleaning your device. Plan ahead when traveling and avoid using tap water in areas with poor water quality.