What is the difference between CPAP and BIPAP

Both CPAP and BiPAP are treatments for sleep apnea that use airway pressure to treat pauses in breathing during sleep. Each technology has unique benefits that is used to treat sleep disordered breathing problems. While there are differences between the two, there are also many similarities.

What is CPAP?

CPAP stands for continuous positive airway pressure. It is the most popular treatment for obstructive sleep apnea (OSA). It uses air pressure generated by a machine, delivered through a tube into a mask that fits over the nose or mouth.

What is BiPAP?

BiPAP refers to Bilevel or two-level positive airway pressure. Like CPAP, air is sent through a tube into a mask that fits over the nose. While CPAP generally delivers a single pressure, BiPAP delivers an inhale pressure and an exhale pressure. BiPAP is a trademark of Respironics.

Which is better, CPAP or BiPAP?

Each is used for a special purpose. Historically, BiPAP was more expensive than CPAP. BiPAP is often used when CPAP is not tolerated by the user. There are new technologies that increase comfort with CPAP.


BiPAP is sometimes used in patients who have pulmonary (lung) issues, like COPD. The difference in pressures helps to eliminate extra CO2 carbon dioxide gas from the body.

CPAP and BiPAP machines look similar. The attachments are the same.

There are other type of ventilatory support devices, including Adaptive Servo Ventilation (ASV).

ASA sponsor

CPAP Masks


Philips DreamCPAP



Old content – To be modified or deleted:

The CPAP machine is designed to deliver air pressure through the nostrils into the back of the throat in order to keep the airway open. The pressure is adjustable. There are several potential modifications to the way the air can be delivered in order to keep the airway open during sleep.

The BiPAP or bilevel machine is very similar to the C-PAP machine. Utilizing the identical setup as a CPAP with tubing and masks, the BiPAP uses a different pressure setting. While CPAP delivers one pressure, BiPAP delivers two pressures. These two pressures are known as inhalation positive airway pressure (IPAP) and exhalation positive airway pressure (EPAP).

cpap bipap
cpap bipap

BiPAP is often used with individuals who need extra respiratory support. It is often prescribed for patients with congestive heart failure/coronary artery disease and pulmonary or neurologic medical disorders. Patients with neuromuscular disorders may also benefit from the pressure differential of a bilevel positive airway pressure device.

The BiPAP is usually preset with two settings. The effort when inhaling and exhaling is monitored. When the  person sleeping doesn’t breathe for a programmed period of time, the BiPAP may be set to deliver a breath. This is usually set as a minimum breath or ‘back-up rate’ that sets a minimum breaths per minute (BPM).

This setting is designed so that the patient breathes a set frequency of breaths per minute. One of the many  advantages of the BiPAP machine is that the strain is decreased during expiration. This limits the amount of energy expended during exhalation. In other words, it is easier to breathe out with BiPAP than with CPAP.

New BiPAP machines are similar in size to CPAP devices. They are about the size of a lunchbox. Many are very quiet. They’re designed to be silent so as not to interrupt the sleeper. Most BiPAP units offer a humidifier option to prevent the drying of the mucosal membranes.

CPAP, BiPAP machine
CPAP, BiPAP machine

In summary, the primary difference between CPAP and BiPAP, or bilevel, machines is the pressure differential. While CPAP has one pressure. BiPAP has two pressures. The ordering sleep physician usually decides what type of breathing treatment should be used. A sleep study often aids in the decision making of this process.

Disclosure: Some compensated affiliate links on this website. We receive compensation in the form of commissions or other payment from some of the companies whose products we list.

BiPAP is a trademark of Respironics and is a promotional partner of ASA.

What are the similarities between CPAP and BiPAP?

CPAP and Bilevel PAP both use air pressure for the treatment of sleep disordered breathing. Both use the exact same attachments. This includes the cpap mask, hose, filter, humidifier. Both sleep breathing machines now come in portable versions which can be transported very easily. Both can be used for treating obstructive sleep apnea.

Share This:

4 thoughts on “CPAP vs BiPAP

  1. Many people used to find bipap more comfortable than cpap. That was during the olden days. Now, the new CPAP machines have settings that allow them to be more comfortable. C-flex and similar technologies have revolutionized how we make cpap more comfortable for patients.

  2. what happens if you can’t stand stuff on your face but really need something to help you breathe? is oxygen better or cpap machine I have copd .. I wake up lots of times at nite with a mouth so dry tongue is stuck to the roof of my mouth and I can’t breathe… mouth so dry I can’t swallow either.. so what next?

  3. I’m curious why my dr. didn’t order the Bipap instead of the cpap. in reading it looks like the bipap would have been better suited for me, since i do have COPD, and had lung cancer in 2013 with the removal of lower left lobe of my lung. a bit confused

Leave a Reply

Your email address will not be published.