Can You Use a CPAP Without Water Illustration

Can You Use a CPAP Without Water? (2024)

by | Updated: May 23, 2024

Continuous positive airway pressure (CPAP) machines are a mainstay treatment for sleep apnea and other sleep-related breathing disorders, ensuring steady airflow and uninterrupted breathing throughout the night.

Central to the operation of many CPAP machines is the humidifier component, which adds moisture to the air and enhances user comfort.

A common question, though, is whether a CPAP machine can be effectively used without water in the humidifier.

This article breaks down the benefits and drawbacks of using a CPAP without water and offers guidance on making the best choice for individual needs.

Can You Use a CPAP Without Water?

Yes, you can use a CPAP machine without water. The water in CPAP devices is primarily for humidification, preventing dryness and discomfort in the airway. While using it dry might be suitable for some, especially in humid conditions, others may experience increased discomfort or dryness. Always consult with a healthcare professional about the best way to use your device.

Wearing a CPAP mask vector

Pros and Cons of Using a CPAP Without Water

CPAP machines are essential for those with sleep apnea and other respiratory issues. Here are the advantages and drawbacks of using a CPAP without water.


  • Less Maintenance: Without water, there’s no need to clean the humidifier chamber as often, reducing the risk of mold or bacteria growth.
  • Travel-Friendly: Carrying water or seeking distilled water can be cumbersome during travel. Without the need for water, the device becomes more travel-friendly.
  • Reduced Leak Issues: Without the humidifier component filled, there might be a reduction in potential leak issues related to the water chamber.


  • Dryness and Discomfort: Without humidification, users might experience dry mouth, throat, or nasal passages, leading to discomfort.
  • Increased Risk of Irritation: The dry air can cause irritation in the nasal passages or throat, possibly leading to nosebleeds or sore throat.
  • Less Effective Therapy: For some users, the absence of humidification might make the therapy less tolerable, leading to reduced adherence.

Note: While there are benefits to using a CPAP machine without water, there are also significant drawbacks. The decision should be individualized, considering one’s comfort and the potential health implications.

What is a CPAP Humidifier?

A CPAP humidifier is an integrated or attachable component of a CPAP machine designed to add moisture to the air that is being delivered to the user.

Its primary function is to prevent dryness and irritation in the nasal passages, throat, and mouth resulting from breathing in the dry air produced by the CPAP machine.

The humidifier works by heating a chamber of water, which then vaporizes, adding moisture to the air the patient breathes in. By doing so, it enhances comfort and increases the likelihood of consistent and prolonged CPAP use.


The benefits of using a CPAP humidifier include:

  • Enhanced Comfort: Moistened air can reduce the sensation of dryness in the throat, nose, and mouth, making the CPAP therapy more comfortable for users.
  • Prevention of Dryness: It helps to prevent or reduce dry mouth and throat, which can be common side effects of CPAP therapy without humidification.
  • Reduced Irritation: Moist air minimizes the risk of nasal congestion, irritation, and nosebleeds that can result from dry, non-humidified air.
  • Better Sleep Quality: By making the therapy more comfortable, users might experience fewer interruptions, leading to better overall sleep quality.
  • Improved Adherence: Comfortable therapy can result in higher adherence rates, meaning users are more likely to use their CPAP machines consistently.
  • Protection for Sensitive Tissues: The moist air helps to keep the mucosal tissues of the nasal passages and throat healthy, minimizing potential damage from dry air.
  • Reduced Inflammation: By preventing dryness and irritation, the humidifier can reduce the chances of swelling or inflammation in the airways.

Note: Overall, a CPAP humidifier can significantly enhance the experience of using a CPAP machine, making the therapy more effective and pleasant for the user.

Tips for Using a CPAP Humidifier

Using a CPAP humidifier effectively requires some knowledge and maintenance.

Here are some tips to get the most out of your CPAP humidifier and ensure a comfortable and safe experience:

  • Use Distilled Water: Distilled water reduces the risk of mineral deposits in the humidifier chamber, which can lead to bacterial growth and shorten the lifespan of the chamber.
  • Clean Regularly: Clean the humidifier chamber at least once a week to prevent mold and bacteria buildup. Some users prefer to clean it daily for optimal hygiene.
  • Empty Daily: Pour out any unused water daily and refill the humidifier chamber with fresh water to ensure cleanliness.
  • Check Water Levels: Ensure there’s enough water in the humidifier for the entire night. However, avoid overfilling, which could lead to water entering the main machine or mask.
  • Adjust Humidity Levels: Most modern CPAP machines allow users to adjust humidity levels. Start at a mid-level setting and adjust based on comfort. If you’re experiencing condensation in your mask or hose (often termed “rainout”), you might want to decrease the humidity level or invest in a heated hose.
  • Regularly Inspect for Damages: Check the humidifier chamber for wear, cracks, or any damage. Replace it if any defects are observed to prevent leaks.
  • Use a Heated Hose: This helps to maintain the temperature of the humidified air as it travels from the machine to your mask, reducing the chance of rainout.
  • Position the CPAP Correctly: Ensure your CPAP machine is placed on a level surface lower than your sleeping position. This prevents water from flowing back into the hose or mask.
  • Be Travel Ready: If you’re traveling, consider whether you’ll have access to distilled water. Some users prefer to travel with a portable bottle of distilled water or utilize the machine without the humidifier in situations where distilled water is inaccessible.

Remember: The primary purpose of the CPAP humidifier is to provide you with a comfortable and effective therapy experience. Regular maintenance and appropriate usage will ensure it serves this role without introducing any complications.

FAQs About Using a CPAP Without Water

How Does a CPAP Humidifier Work?

A CPAP humidifier adds moisture to the air that the CPAP machine delivers to the user. It operates by heating a chamber filled with water.

As the water heats, it vaporizes, and the machine then pushes air through this chamber, picking up the moisture in the form of water vapor.

This humidified air is delivered to the user, ensuring the airways do not dry out during therapy.

What is the Importance of CPAP Humidification?

CPAP humidification is crucial in ensuring user comfort and adherence to therapy.

Breathing in dry air for extended periods, especially during sleep, can cause dryness, irritation, and discomfort in the nasal passages, mouth, and throat.

By adding moisture to the air, the humidifier prevents these issues, making the therapy more tolerable and effective. Moreover, humidified air aids in maintaining the health of the mucosal tissues in the respiratory tract.

What Happens If I Don’t Use Water in My CPAP Machine?

If you don’t use water in your CPAP machine, it means you’re bypassing the humidification process. While the machine will still deliver air at the prescribed pressure, this air won’t be moisturized.

As a result, you might experience increased dryness in your mouth, nose, and throat. Over time, this can lead to discomfort, irritation, nasal congestion, or even nosebleeds.

However, the exact effects can vary depending on individual sensitivity and the ambient humidity of the environment.

What Can I Use Instead of Water for My CPAP?

It’s essential to use only water in your CPAP humidifier. Introducing other liquids can damage the machine, lead to bacterial or mold growth, or cause harmful substances to be inhaled.

If you’re traveling or in a location where distilled water is unavailable, using bottled or tap water temporarily is permissible.

However, you should thoroughly clean the humidifier chamber afterward to prevent mineral buildup.

Who Needs a Humidifier for Their CPAP Machine?

While many CPAP users benefit from a humidifier, it’s particularly recommended for:

  • Individuals in dry or arid climates.
  • People who frequently experience dry mouth, throat, or nasal passages during or after therapy.
  • Those who have reported irritation, such as nosebleeds or nasal congestion, with CPAP use.
  • Users who find CPAP therapy uncomfortable or intolerable without moisture.

Note: It’s essential to understand that individual needs can vary. Some users in humid environments might not find a humidifier necessary, while others, regardless of climate, might prefer humidified air for comfort.

Do I Need Distilled Water for My CPAP Humidifier?

Yes, distilled water is the recommended type of water for CPAP humidifiers. Distilled water lacks the minerals found in tap water, preventing mineral buildup in the humidifier chamber.

This not only extends the life of the chamber but also reduces the risk of bacterial and mold growth.

If distilled water isn’t accessible, purified or bottled water is a temporary alternative, but always ensure the humidifier is cleaned regularly to avoid mineral deposits.

Jug of Distilled Water Vector

How Often Should I Change the Water in My CPAP Humidifier?

You should change the water in your CPAP humidifier daily. Empty any leftover water each morning and refill with fresh distilled water before your next therapy session.

Regularly changing the water helps ensure you’re breathing clean, humidified air and also reduces the risk of bacteria or mold growth in the water chamber.

Can You Use a ResMed CPAP Without Water?

Yes, you can use a ResMed CPAP machine without water. If you choose not to use the humidification feature or if the water chamber is empty, the device will still deliver the prescribed air pressure.

However, remember that forgoing water means you’re missing out on the benefits of humidification, which may lead to dryness and discomfort in the nasal passages and throat.

What are the Problems of Not Using a Humidifier with a CPAP Machine?

Choosing not to use a humidifier with a CPAP machine can lead to several issues:

  • Increased Dryness: Users may experience dry mouth, throat, or nasal passages, which can be uncomfortable and may disrupt sleep.
  • Irritation and Congestion: The dry air might cause irritation in the nasal passages or throat, potentially leading to nosebleeds, sore throats, or nasal congestion.
  • Reduced Adherence: Some users find CPAP therapy with dry air less tolerable, which could result in inconsistent use or abandoning the therapy altogether.
  • Mucosal Damage: Prolonged exposure to dry air can potentially harm the mucosal tissues in the respiratory tract.

What Kind of Water is Best for CPAP?

The best water for CPAP machines is distilled water. Distilled water has had its impurities and minerals removed, ensuring that there’s no mineral buildup in the humidifier chamber.

This helps to prolong the chamber’s life and reduce the chances of bacterial or mold growth.

Is It Better to Use Hot or Cold Water for CPAP?

When filling the CPAP humidifier chamber, you should use room-temperature distilled water.

The CPAP machine itself will heat the water to the desired level of humidification.

Using hot or cold water is unnecessary and not recommended, as the machine is designed to heat the water to an appropriate and safe vaporizing temperature.

Do I Need to Empty CPAP Water Every Day?

Yes, you should empty any remaining water from your CPAP humidifier chamber daily. This ensures that you’re using fresh water each night and reduces the potential for bacteria or mold to grow in standing water.

After emptying the chamber, it’s good practice to let it air dry before refilling it for the next use.

Can I Use Tap Water in CPAP for One Night?

While distilled water is always the best choice, using tap water for one night in a pinch is generally acceptable.

However, tap water may contain minerals and impurities that can leave deposits in the humidifier chamber or promote bacterial growth.

If you must use tap water temporarily, make sure to empty the humidifier chamber, rinse it thoroughly, and let it dry to minimize any potential buildup.

Final Thoughts

While it’s technically possible to use a CPAP machine without water in its humidifier, doing so might not be suitable for everyone.

The primary function of the humidifier is to provide moisture, preventing dryness and irritation in the airway.

For users in humid climates or those who tolerate dry air well, skipping the water might be an option. However, for the vast majority, using water is recommended to ensure comfort and maintain airway health.

Always consult with a medical professional before making changes to CPAP usage to ensure safety and efficacy.

John Landry, BS, RRT

Written by:

John Landry, BS, RRT

John Landry is a registered respiratory therapist from Memphis, TN, and has a bachelor's degree in kinesiology. He enjoys using evidence-based research to help others breathe easier and live a healthier life.


  • Hooper RG. CPAP Therapeutic Options for Obstructive Sleep Apnea. Pragmat Obs Res. 2020.
  • Raymond LW, Barkley JE, Langley R, Sautter R. Prolonged respiratory illness after single overnight continuous positive airway pressure humidification: endotoxin as the suspect. South Med J. 2009.

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