BiPAP vs CPAP - Which One is Best?

One of the most common questions our patients ask here at CPAP Supplies is “what is the difference between CPAP and BiPAP?” Both machines are used to treat sleep apnea and can be used with a full face mask, nasal mask, and nasal pillows.  Both use positive air pressure to promote airflow while you sleep. Yet for some, the difference between the two is the key to better sleep

If CPAP therapy just isn't working for you, a BiPAP could be the solution you need. Keep reading to find out if BiPAP therapy is right for you.

What is CPAP?

CPAP stands for Continuous Positive Airway Pressure because CPAP machines have a “fixed” or constant level of pressure. This constant stream is used to keep the airway open during sleep, thus preventing apneas, or pauses in breathing due to relaxed muscle tissue in the laryngeal/tracheal region.

Though the pressure level can be adjusted, it will only deliver a single pressure throughout the night. This pressure level will be determined by your doctor, sleep specialist, or other healthcare professional. 

CPAP devices are the most commonly prescribed treatment for Obstructive Sleep Apnea (OSA) because CPAP therapy is the most effective non-invasive option.

What is BiPAP?

BiPAP machines– or Bilevel Positive Airway Pressure– are different from CPAP machines because, as the name suggests, it has two set levels of pressure. 

The first level of pressure is inspiratory positive airway pressure (IPAP). This higher pressure level is applied during inhalation to keep the air passage open. The second level of pressure is expiratory positive airway pressure or (EPAP), and this lower pressure level is more natural to help with exhaling.

BiPAP machines are more typically prescribed to patients who have additional health concerns. These may be more complicated sleep disorders, such as Central Sleep Apnea or Complex Sleep Apnea, or cardiopulmonary conditions such as Chronic Obstructive Pulmonary Disease (COPD) or a history of congestive heart failure.


The machines may look identical, but now you can see that the difference between the two is in how they use pressurized air. A CPAP machine delivers pressure at one level and a BiPAP machine can fluctuate between two different pressures.

The lower pressure during exhalation may help to avoid some potential side effects of PAP therapy, such as difficulty exhaling, bloating, dry mouth, and sinus discomfort. For this reason, BiPAP therapy is sometimes prescribed to apnea patients who have difficulty adjusting to fixed CPAP pressure.

This might make you think that a BiPAP is the better option, but it may not be right for you! BiPAP machines often tend to be significantly more expensive, and may not be covered by your insurance provider.

If adjusting to the airflow is your only concern, you may be better off with an APAP, or Automatic Airway Pressure Machine.

CPAP and APAP Options

Many patients succeed with CPAP treatment that utilizes one level of pressure and have experienced great benefits from using their CPAP machine. Yet you may also benefit from an APAP, which can automatically adjust the level of your pressure during the night. carries a wide variety of standard CPAP machines and APAP machines.

If you are having trouble adjusting to your CPAP machine, there are a few things to consider before deciding to try a different treatment option:

  • Make sure that you have a well-fitting CPAP mask. Many patients cannot tolerate their machine simply because they have a mask that does not properly fit them. Use our handy mask fit guide to ensure that you get a great fit.
  • Check your humidity level and remember to use your ramp button. The ramp feature will lower your pressure and slowly work its way back up, giving you time to fall asleep at a comfortable pressure.

Consider a BiPAP Machine

If you are still having trouble with your CPAP machine, it may mean that you are a BiPAP candidate. BiPAP machines are a great option if you require a high-pressure setting. If you've experienced CPAP failure, your insurance might cover a BiPAP upgrade. carries a great selection of standard BiPAP and Auto BiPAP machines. We offer patient-pay pricing or you can qualify through your insurance for your equipment. No matter what needs you have when it comes to sleep apnea treatment, will help you find the best equipment at the right price.