Sleep Education

American Academy of Sleep Medicine 

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CPAP - Variations

Types of PAP therapy

There are several forms of positive airway pressure (PAP) therapy other than CPAP. All forms of PAP therapy keep your airway open as you sleep by providing a stream of air through a mask that you wear:


Autotitrating positive airway pressure (APAP) therapy automatically raises or lowers your air pressure as needed during the night.


Bilevel positive airway pressure (BPAP) devices have two alternating levels of pressure. When you breathe in air, the pressure rises. The pressure decreases as you breathe out. If you have a problem with CPAP or APAP, your sleep doctor may recommend BPAP. Your doctor also may recommend using BPAP if you have sleep apnea along with another breathing disorder.

Types of Masks

There are three common types of CPAP masks. No matter what type of mask you use, it is important that it fits well and is comfortable.

Nasal mask

This mask only covers your nose. This is the most common type of CPAP mask.

Full face mask

This mask covers both your nose and your mouth. This type of mask may help if you have air leaks when using a nasal mask.

Nasal pillows

This mask uses soft silicone tubes that fit directly in your nose. This may help if you have air leaks or don’t like the feeling of a mask over your nose and face.


Humidifiers for CPAP can help reduce side effects from the treatment and make it easier for you to breathe through your mask. Some people may have nasal irritation or drainage from using CPAP. A humidifier can reduce these side effects by providing cool or heated moisture to the air coming from the CPAP unit. Many CPAP units come with a humidifier connected to the machine.

Updated Aug. 10, 2015

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