Do I Need a Humidifier for my CPAP

cpap humidifier

The majority of CPAP machines are equipped with fully integrated or easily attached humidifiers. 

Humidifiers are meant to make CPAP therapy more comfortable and increase compliance with therapy. There are other benefits to humidification that make your CPAP therapy more effective.

Why Does My CPAP Need A Humidifier?

There are certain conditions that lead to sleep apnea patients using CPAP treatment to develop dry, irritated airways and even nosebleeds.  

There are several reasons why you might need a humidifier for your CPAP machine, including:

  1. You live in a dry climate.
  2. You are over the age of 60, which makes you five times more likely to suffer from these issues.
  3. You are taking medications that dry out the sinuses, making it six times more likely to suffer from dry airway issues.
  4. You have a chronic mucosal disease, postnasal drip, or sneezing.
  5. You have had your uvula removed surgically.
  6. If using your CPAP makes you –
  • Sneeze
  •  Have a dry mouth
  •  Experience burning nasal passages
  •  Disrupts your sleep due to any of the above symptoms
  •  Have a runny nose
  • Have a stuffy nose
  • Experience frequent nosebleeds
  • Wake up with mucus in your mouth and throat

All of the symptoms in this list can be resolved by using a humidifier with your CPAP machine. Heated moisture softens the nasal passage and makes the pressurized air more comfortable to breathe.

Nasal Resistance and Mouth Breathing

The reason that most people breathe through their nose at night isn’t just because they’re born with a natural inclination to do so. Sometimes, it’s due to dry airways or untreated sleep apnea.

If your nasal passage is dry or congested from your CPAP machine, you can end up breathing through your mouth, which causes more dryness and discomfort. 

Depending on what type of CPAP mask you use, you can also end up with substantial air leaks from mouth breathing while you’re asleep. 

There are some individuals who become chronic mouth breathers after they develop sleep apnea and stay that way even after treatment. Because sleep apnea causes short periods of hypoxia (a state where your oxygen levels drop when you stop breathing), you start sleeping with your mouth open to accommodate your body’s need for more oxygen.

Our noses are natural humidifiers. When we breathe in through our nose, the outside air is heated to body temperature to make it more comfortable and avoid damaging the sensitive tissues in our airways and lungs. 

Inhaling cold air wakes us up, whereas warm air does not. The pressurized air released from a CPAP machine enters the lungs faster than the nose can heat the air, so it must be heated externally through the machine.  \

This can be especially true in dry climates or for patients who require high CPAP pressures.

Humidification Increases CPAP Treatment Compliance

Humidification involves warming and moistening the air you’re breathing through your CPAP machine. 

It reduces the dryness in your nose and throat and helps to keep your mouth closed while you sleep. It also improves the comfort level of sleeping with a CPAP mask on.

Research shows that CPAP compliance is significantly greater when heat and humidity are used. This increased treatment compliance is most likely due to reduced airway irritation, dry mouth, and coughing upon waking. Patients over the age of 60 are often on medications that cause dry mouth as a side effect and benefit from the humidified air.

CPAP treatment with humidification is simply more comfortable. The more comfortable it is, the more likely patients are to use it.

History of CPAP Humidifiers

CPAP machines were invented for the treatment of sleep apnea in the 1980s. The air was initially humidified by a chamber of room-temperature water that the CPAP air was passed through. 

This method of humidification is called passive humidification, where the air was supposed to pick up evaporated moisture in the water chamber. This method, however, isn’t very effective.

Heated humidification was developed for CPAP machines in the mid-1990s. This involved heating the water in the chamber to create more evaporated moisture to be absorbed. This is the type of humidification used in CPAP machines today. It is either an attachment to the machine or built right in. 

Side Effects of CPAP Humidifiers

There are two primary side effects of CPAP humidifiers:  the first is that you still experience dryness symptoms when the temperature and humidity settings are too low.  The second and more frequent side effect is called rainout.

Rainout occurs when the heated air in your CPAP cools off in the tubing and condenses back into the water.  

The result is that only water reaches your CPAP mask instead of heated air. This can be avoided by using a tube that is heated and adjusting the tubing temperature and level of humidity being provided in the water chamber.

Quick Facts About CPAP Humidifiers

  • Patients over 60 are five times more likely to need humidification.
  • CPAP users who are on two or more prescription medications are six times more likely to require heated humidification.
  • CPAP users with the chronic mucosal disease are four times more likely to need heated humidification.
  • Patients who sleep in cold rooms need condensation, as cold air causes airway and lung irritation.

When You Would NOT Need A CPAP Humidifier

There are certain times when you can use your CPAP without a humidifier.  Your CPAP will function normally with the humidifier off or unattached and will still be an effective treatment for your sleep apnea.

  • When you are traveling, you may want to leave your CPAP humidifier at home. It can cause extra weight in your luggage, and you may not be able to access distilled water for proper usage.
  • If you live in a particularly warm and humid environment, you may not need a humidifier, as the outside air is already heated and humidified.
  • Some long-term CPAP users become used to the side effects and no longer feel a humidifier is necessary. If you have no issues with treatment compliance, you may feel it’s unnecessary.


Dan was diagnosed with sleep apnea in 2017 when he was only 32 years old. He has been using a BIPAP machine for his treatment. He hopes to provide a patient's perspective on the sleep apnea experience. Dan lives in Tampa with his girlfriend and 2 dogs.

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