Should You Use Distilled Water for a CPAP Machine?

Benefits of Using a CPAP Humidifier

The continuous flow of air that comes from a CPAP machine can feel drying. Some CPAP users report irritation in their nose and throat, including nose bleeds, sinus congestion, and dry mouth. A CPAP humidifier adds water to the pressurized air to increase humidity and make breathing with a CPAP device more comfortable.

If you use a CPAP machine and routinely wake up with dry breathing passages, you may want to consider adding a humidifier to your CPAP setup. It is also critical to regularly clean your CPAP machine, including your mask and other device components.

Why You Should Use Distilled Water in a CPAP Machine

While tap water is readily accessible and may be tempting to use in your CPAP humidifier, it can contain mineral deposits and other chemicals that may damage your machine or result in potentially harmful bacterial growth Trusted Source National Library of Medicine, Biotech Information The National Center for Biotechnology Information advances science and health by providing access to biomedical and genomic information. View Source . In terms of bottled water options, they can be boiled down to the following categories:

• Purified water: Most bottled water is purified, meaning it is filtered to remove chemicals, though it may still contain some mineral content Trusted Source United States Environmental Protection Agency (EPA) The mission of EPA is to protect human health and the environment. View Source . Most purified drinking water sold in stores originates as municipal tap water. Some brands employ a reverse osmosis Trusted Source Centers for Disease Control and Prevention (CDC) As the nation’s health protection agency, CDC saves lives and protects people from health threats. View Source process, which removes impurities and microbes by using pressure to force water through a semipermeable membrane. Bottled water produced through these purification methods is often remineralized to provide healthy minerals for drinking.
• Spring water: Generally rich in mineral content, spring water comes from aquifers and is naturally filtered underground before it reaches an above-ground spring. Artesian water is similar to spring water, but it comes from an artesian well that taps an aquifer.
• Mineral water: Mineral water sold in the U.S. must come from an underground water source and needs to contain a minimum amount of total dissolved solids Trusted Source U.S. Food and Drug Administration (FDA) The FDA is responsible for protecting the public health by ensuring the safety, efficacy, and security of human and veterinary drugs, biological products, and medical devices; and by ensuring the safety of our nation's food supply, cosmetics, and products that emit radiation. View Source to be branded as such.
• Distilled water: Considered the purest form of bottled water, distilled water is produced by boiling water and then condensing the vapor back into liquid form.

Distilled water is the best choice for CPAP humidifiers because it’s pure water that is free of minerals and bacteria. Hospitals, labs, and factories often use distilled water instead of tap water because it prevents limescale buildup on devices.

Using the wrong type of water in your CPAP humidifier can cause mineral buildup, scaling, or bacterial growth. It may also irritate your airways or cause your machine or its components to break down.

Is It Better to Buy Distilled Water Instead of Distilling It Yourself?

Though distilling water is fairly simple to do at home, it’s generally best to purchase distilled water for use in your CPAP humidifier. Labs and factories have quality control procedures that ensure each bottle of distilled water is processed correctly before it’s sold to consumers. When you distill water at home, you don’t have these safeguards.

Does Purified or Filtered Water Work as a Substitute for Distilled Water?

Purified or filtered water can contain minerals that may lead to buildup in your CPAP machine, so it’s best to use distilled water. The distilling process eliminates minerals, chemicals, and bacteria, leaving the purest possible water behind.

Best Place to Buy Distilled Water

Distilled water is easy to find. Most grocery stores, drug stores, and mini-markets carry distilled water. You can also buy it from online stores and CPAP suppliers. Some online retailers offer subscriptions so that you don’t have to worry about reordering or running out.

Why Tap Water Is Not a Substitute for Distilled Water

Tap water can come from a well or a municipal water supply. Though your tap water may be perfectly fine to drink, it may contain minerals that can cause buildup or scaling in your CPAP machine. Tap water may also contain additives like chlorine or fluoride that can harm your machine.

While you can boil water to kill bacteria, it will still contain any mineral content that was there prior to boiling.

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