What Is a BiPAP?

Medically Reviewed by Melinda Ratini, MS, DO on March 03, 2022

If you have sleep apnea or another condition that affects your breathing, your doctor might have mentioned a bilevel positive airway pressure machine, or BiPAP, to you. Sometimes called a BPAP, it's a device that helps you breathe.

How Does a BiPAP Work?

When you take in air, your diaphragm -- a muscle in your chest that helps you breathe -- moves downward. This drops the pressure in the tubes and sacs in your lungs and draws air into them. If you have a condition like sleep apnea, there may be times (like while you’re sleeping) when you can’t draw in the air you need.

In that case, your doctor may recommend that you use a BiPAP. It pushes pressurized air into your lungs. That opens them and lets you get the oxygen you need, which can lower your chances of things like a heart attack.

A BiPAP machine is about the size of a lunchbox. A face mask, nasal mask, or nasal plugs are attached to the machine by a tube. The machine motor blows air through the tube. The air enters your body through the mask or plugs. Some BiPAPs have other technology, like a humidifier.

Using a BiPAP might be uncomfortable at first. But most people get used to it over time. If you feel like you can’t breathe when you’re wearing your BiPAP, contact your doctor right away. Adjusting the settings on your machine may do the trick.

Who Uses a BiPAP?

You may benefit from a BiPAP if you have a medical condition that makes it hard for you to breathe sometimes. BiPAPs can be helpful for obstructive sleep apnea, a serious condition where your breathing stops and starts repeatedly while you’re sleeping. In some cases, it can be life-threatening.

Your doctor may also recommend a BiPAP if you have:

If you have trouble breathing most or all of the time, or have trouble swallowing, a BiPAP probably isn’t for you. Instead, your doctor may recommend another device to help you get enough air.

BiPAP vs. Other Breathing Machines

A BiPAP isn’t the only type of ventilator that uses positive pressure to help you breathe. Another common breathing device is the continuous positive airway pressure machine, or CPAP. Both deliver air pressure when you breathe in and breathe out. But a BiPAP delivers higher air pressure when you breathe in. The CPAP, on the other hand, delivers the same amount of pressure at all times. So the BiPAP makes it easier to breathe out than the CPAP. Still, In order to help with the discomfort of CPAP's continuous flow of air pressure upon exhalation, most manufacturers offer the ability for the machine to sense and/or reduce the pressure upon exhalation."

APAP, an auto-titrating CPAP, also delivers varying amounts of positive airway pressure and should only be prescribed after careful consideration

Some people with sleep apnea or similar breathing problems may use a CPAP first. But in some cases, a BiPAP may be a better choice if you need more help breathing because of severe sleep apnea or a condition like congestive heart failure.

If you do have a sleep disorder like sleep apnea, a sleep study can help your doctor figure out which device is best for you.

BiPAPs tend to be more expensive than CPAPs, though your insurance may cover some or all of the cost for the device. If you’re not sure, or you want to know about using a different breathing device than you’re using, talk with your doctor.

Will I Always Have to Use It?

It’s important to follow your doctor’s instructions on how and when to use your BiPAP. If your health problems and breathing improve, you may be able to lower the pressure on your machine or use it less often. Your doctor will work with you to figure out when it’s time for a change.

Show Sources


Johns Hopkins Medicine: “BiPap.”

American Sleep Association: “What is the difference between CPAP and BIPAP?”

University of Rochester Medical Center: “BiPap.”

Cleveland Clinic: “Why Sleep Apnea Increases Your Risk of Sudden Death.”

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