Expiratory Positive Airway Pressure Devices

Expiratory positive airway pressure, also known as EPAP, is a type of snoring therapy that is supposed to work similarly to CPAP, except that it uses the body’s own breathing mechanisms to supply the pressure instead of an outside machine.

EPAP devices, therefore, are devices that use the body’s own airway pressure to help treat snoring and/or sleep apnea. These types of devices take many forms. There are, for example, nasal dilators that you put in your nostrils that have tiny valves on them. These valves allow you to breathe in normally, but make breathing out more difficult.

Theravent Nasal Dilators

The idea is that this builds up a certain amount of airway pressure in your respiratory system, and that this pressure can help you to avoid the dangerous effects of snoring.

It was first introduced in the mid 2000s, and has grown in popularly since then.

How Is EPAP Technology Meant To Work?

So the idea behind EPAP is pretty much the same as the idea behind a CPAP machine – except that the pressure comes from different places. In a CPAP machine, pressure comes from an external device… while with EPAP technology, the pressure comes from the pressure created by one’s own breathing.

EPAP devices basically help to trap exhaled air in the airway, which is supposed to expand the soft palate and keep the loose tissues and muscles from restricting airflow.

CPAP and BiPAP Differences

Snoring and sleep apnea are usually caused by a phenomenon known as ‘soft palate vibration.’ This occurs when loose tissues and muscles in the airway relax and collapse-in, thereby restricting air movement. This causes the air to vibrate those loose tissues – which produces the sounds that we have come to know as snoring.

But creating pressure in the airway is said to be able to help ‘push back’ this loose tissue, and keep it out of the way. So EPAP technology seeks to accomplish this by using exhaled air to build-up pressure.

Do We Believe That This Method Works?

This seems to be a hit-and-miss method, as far as we can tell. For some people, it works quite well. But it kind of depends on the type of device being used, and on how the technology is being applied. CPAP technology is proven to work for sleep apnea, but that is different. So, the difference is in how the pressure is created.

It seems that exhaled air, in combination with the devices used to harness it, does not always do enough to make a big difference.

It can… but it is not 100% for sure. It really depends on the device and on the person trying to use it. We have seen some success with these types of devices. But in truth, we have seen much better results with mandibular advancement devices and tongue retention devices than with EPAP devices.

The Positives

Here are the main upsides to this type of device…

  • It does not require a machine like CPAP does
  • It is relatively non-invasive
  • It is inexpensive (especially when compared to CPAP)
  • It doesn’t require you to have anything in your mouth while you sleep

The Negatives

Here are the major downsides to this type of device…

  • It is simply not as effective as some other types of snoring therapy
  • You may not be as likely to experience relief with EPAP as you are with other types of treatments
  • It is not very helpful if you are suffering from nasal snoring problems
  • There are not a ton of devices that make use of this technology anyway

Who Should Use EPAP Device, And When?

The best candidates for this type of product are going to be people who have trouble with snoring that is caused by soft-palate vibration. Products that make use of EPAP technology are also going to be best used by adults who, for some reason, do not feel that CPAP is the right choice for them (probably because it is too invasive or because it is too expensive).

But this type of product might also be popular with people who feel like they would rather not go for something terribly invasive right from the beginning. If you are not super into the idea of having something in your mouth, then this type of device is actually not so different from a regular nasal dilator, except that it actually treats soft palate vibration… not nasal snoring, so that makes it kind of unique.

As for when to use the product – it would need to be used every night during sleep in order for you to start noticing the benefits.

Who Should Avoid This Type Of A Product?

This type of product is probably not going to be as useful for people who suffer from nasal snoring. It is also not going to be as useful for people who don’t want anything in or around their nasal passages, as that is how most of these products work.

If you want more technical results, you may also find better luck with an MAD or a tongue retention device.

Is There Any Clinical Evidence That EPAP Works?

There have been a few different studies on EPAP technology. One of the most-often-referenced studies on the books was titled Long-Term Use of a Nasal Expiratory Positive Airway Pressure (EPAP) Device as a Treatment for Obstructive Sleep Apnea (OSA). It was published in the Journal of Clinical Sleep Medicine, back in 2011.

It was intended to ‘evaluate the long-term durability of treatment response and safety of a nasal expiratory positive airway pressure device used to treat obstructive sleep apnea.’ As you likely know, obstructive sleep apnea is actually a lot worse than regular snoring… though the two can often be found hand-in-hand.

Heavy snoring does not always indicate a problem with obstructive sleep apnea… but it is one of the strongest indicators of the condition.

This particular study pitted an actual EPAP device against a sham device in a randomized clinical trial. The results were collected from 13 sites, which included academic sites and private sleep disorder centers.

The results were pretty conclusive. As it turned out, Nasal EPAP ‘significantly reduced the AHI, improved subjective daytime sleepiness and reduced snoring after 12 months of treatment.’

(Note: AHI stands for ‘Apnea-Hypopnea Index.’ This is an index used to measure the severity of sleep apnea. It basically counts the number of apnea and hypopnea events per sleep hour.)

It was also shown that long-term adherence to EPAP was excellent in those who were faring well with the device at the 3-month mark.

You can view the study material here.

Another often quoted study on the subject of EPAP was published by the Sleep Research Society back in 2011. It was called A Novel Nasal Expiratory Positive Airway Pressure (EPAP) Device for the Treatment of Obstructive Sleep Apnea: A Randomized Controlled Trial, and was designed to ‘investigate the efficacy of novel nasal expiratory positive airway pressure device as a treatment for OSA.’

This test was actually very similar to the above-mentioned test, and discovered similar results. Here is a quote from the discussion portion of the study text.

“The major finding of the study was that the EPAP device significantly decreased the AHI compared to device-off nights on the week 1 sleep study, and that the difference was significantly greater than with the sham device (52.7% versus 7.3%, ITT analysis).”

This study did have some limitations, though. There was a rather wide margin allowed for exclusion criteria, for one.

The second limitation was that adherence determinations depended on patient reports instead of objective measuring.

But all in all, the study just confirms the same facts presented in the afore-mentioned work… that EPAP devices are actually pretty effective at treating obstructive sleep apnea. You can read more about this study here.

The History of EPAP

The person credited with inventing EPAP technology was a doctor and engineer named Rajiv Doshi. The entire thing started when his wife complained of her snoring problems, and asked him if he could do anything about it.

Interestingly, he recalled his days in medical school back in the 90s, when he had, at one point, watched a patient with emphysema do breathing exercises through pursed lips.

The simple breathing exercise helped by creating backpressure to keep airways open while the patient breathed… and this gave the doctor the inspiration he needed for EPAP technology.

As the story goes, he tested a homemade EPAP anti-snoring device for quite a while before coming up with a solution that actually worked. He used materials like tubing, picked up at the local hobby store… along with small bits of latex glove.

Back then, in the mid-2000s, many surgeons were looking for alternatives to the snoring treatments that were available. He wanted to create a less-invasive option than surgery, and succeeded.

The device was eventually released under the name Provent, though a lower-pressure version was eventually released. This version was called Theravent, and millions of units have sold since the product was initially released to the public.

It has since become a pretty well-known therapy among sleep physicians, and is most well known as an alternative to CPAP that doesn’t require you to use a power source. The product is also small enough to fit in the palm of your hand… which is a huge selling point.

It was a simple product that actually worked. And ironically, for this reason, it was initially met with disbelief. But after it went through a few studies and ‘earned its stripes,’ it was accepted and has become incredibly popular.

You can read more about the history of EPAP in this SleepReviewMag.com article, EPAP Gets A New Look.

Is There Any Risk to Using EPAP?

Products like Theravent are extremely low-risk. There is almost no risk associated with putting a little adhesive strip onto your nose… which is partly why they are appealing to people.

Unlike nasal strips, which you stick to the outside of your nose in an attempt to ‘open up’ the nasal passages, Theravent consists of small strips you place over the opening of the nostrils. These little strips contain a vent that allows you to breathe in without any trouble, but that doesn’t allow for a full exhale.

It takes more air pressure to breathe out than in, which is how Theravent creates EPAP backpressure for patients.

And the results are actually pretty awesome!

Some people describe Theravent as the perfect solution if they don’t want to use CPAP or mandibular advancement devices. One particular review we read featured a woman who had a terrible snoring problem… but who didn’t like MADs because they made her gag. This same woman tried CPAP, but complained that the masks always leaked.

So when she tried Theravent, her problems were solved!

You can read the full story here. But it does a pretty good job of explaining why some people prefer EPAP to other types of devices.

In the end, it all just goes to show that there truly is a stop snoring device for everyone. There are MADs, TSDs, CPAP machines, EPAP strips, nasal strips, anti-snoring chin straps, smart snoring solutions, etc.

Thankfully, snoring is getting a lot more attention these days than it used to get. With any luck, society will continue to become aware of the fact that snoring is actually a very dangerous condition… especially if it has graduated to a full-blown case of obstructive sleep apnea.

Sleep apnea can put you at risk for a number of different diseases and conditions, including diabetes, high blood pressure, heart disease, stroke, and others.

If EPAP Doesn’t Work for You, What Should You Try?

EPAP may not be for everyone. And if it ends up not being for you, then rest assured that there are other options out there.

But the best thing to consider first is probably this question. Why did EPAP fail you?

If it failed you because you are actually suffering from nasal snoring, then you may want to try nasal strips to solve your snoring woes.

If it failed you because you are suffering from OSA, and because it just didn’t do enough good to overcome your nightly breathing problems, then CPAP or a mandibular advancement device may be better options for you.

If you tried it, but didn’t like something stuck to your nose while sleeping, you may want to consider a TSD or an MAD.

But there are also ‘smart’ snoring solutions nowadays to look at as well. Our favorite example of this is the ‘Smart Nora,’ which is a device that raises and lowers your pillow while you are sleeping when it detects snoring.

Smart snoring solutions are actually making big waves in the anti-snoring world, and we’ve been looking pretty closely at them… as they pack in a lot of benefits and blend technology with therapy to produce results.

There are literally all kinds of different options out there. All you have to do is take stock of your snoring problems, figure out what is going wrong, figure out what types of products may work the best for you, and give the most obvious first-choice options a try.

Obviously, not every product is going to work the same for everyone. It is also a given that you are going to have to go through at least a little bit of trial-and-error before you reach the perfect product for you. Some people get lucky and find the perfect solution right away. But far more often, people end up trying a few different devices before settling on the one that works the best for them.


If you need a stop snoring method and want to find something that you do not have to put into your mouth while you are asleep, then products using EPAP technology can serve as a possible alternative to CPAP machines, MADs, TSDs, and the like.

They do not have as proven of a track record, but they do work for a lot of people, and you may be able to find a lot of help with your snoring with these types of devices.

If you are a nasal snorer, this is probably not going to be the type of device for you. But, EPAP is awesome for people who suffer from standard soft-palate vibration snoring. It is also an awesome option for people who don’t like the idea of MADs or CPAP.

Plus, Theravent has taken the concept of EPAP and made it even easier to use, which is awesome.

It may not work for everyone, but it can be a pretty seriously useful option for the right person!

Updated 2.5.2019

Josh Sigafus Editor

Joshua Sigafus is just a writer trying to make the world a better place. You can find him on Facebook.