Updated March 09, 2021

Continuous positive airway pressure (CPAP) machines are currently the most recommended treatment for obstructive sleep apnea, and patients often feel major improvement after using them for just one night. But before you decide whether the therapy works for you, it's important to consider the different options available: Where you buy your machine, which type you end up with, and what options are included will all affect how willing you are to use CPAP and how well it will work for you.

Getting a prescription
To get an air pressure machine, you first need to be diagnosed with sleep apnea. This process will probably require an overnight study in a sleep clinic; a home sleep test may be another option.

After your initial sleep study, a technician will measure your body's response to different air pressure, or titration, levels. Most machines range from about 4 to 20 cm H20, meaning that they blow enough air to create a column of water that height.

Your prescription can be filled at a sleep clinic or another equipment retailer. It should include the following details.

  • The type of device—CPAP, BiPAP, or APAP, for example.
  • It can be generic, rather than a name brand or specific model, with some exceptions. "Most CPAP machines are interchangeable and it may take some time to find the best one," says Teofilo L. Lee-Chiong Jr., MD, medical director of the Sleep Center at National Jewish Medical and Research Center in Denver. "If you're not limited to one machine, you can use the prescription for years to try newer models."
  • The correct pressure level. These levels are set before you receive the machine and should only be adjusted by a doctor or technician, never by the patient.

With your machine, you'll usually receive a six-foot hose and carrying case. Doctors might also include a note for a heated humidifier, which makes the harsh airflow more tolerable and reduces side effects such as dry throat and nasal congestion. You can buy a humidifier without a specific prescription, but if it's included on your slip you'll be sure not to overlook it. Masks and other accessories can also be sold without a prescription.

Shopping around
Many centers are equipped to provide you with a CPAP machine immediately after your sleep study, or they can refer you to a local durable medical equipment (DME) supplier that sells or rents them. They'll also fit you for a mask and show you how the whole system works together.

Insurance usually covers or reimburses the cost of the machines, and several online retailers have discounted prices. (Make sure you're ordering from a legitimate site; any retailer that doesn't require a prescription may not be distributing CPAPs legally.)

When Matt Hanover, 44, received his prescription for a CPAP, he felt pressured into taking home the machine that had been used for his sleep study that very same day. "The clinic basically told me I had to buy it from them, even though I still wasn't comfortable with the idea of wearing a mask at night and my insurance didn't cover the whole thing," says Hanover, a digital media producer in Santa Monica, Calif. "I didn't realize that I had other, cheaper options."

Hanover never got used to the CPAP machine and eventually gave up altogether, but he couldn't get any money back from the sleep clinic. To avoid getting stuck, be sure to ask potential retailers if they grant a trial period for equipment and whether it can be returned if it's not a good fit.

Choosing a mask
Once your doctor finds the right air pressure level for your CPAP, the next step is finding a breathing device that fits well and is comfortable enough to wear through the night. There are four main types of CPAP masks, all secured by straps around the forehead and/or chin, with flexible foam or gel cushioning:

• Nasal pillows, or tiny tubes that fit directly into the nostrils
• Nasal masks, which form a seal directly around the nose
• Full-face masks, which cover the nose and mouth
• Oral masks, which are attached between the lips and gums

Jane, 64, a social worker in New York City, has searched for 10 years to find the perfect mask. "I've learned what works for me, so each one I try has been a little better," she says. "I've tried all different kinds and have gotten used to a few pretty good models, but I still read reviews and check message boards, looking for newer ones that might be better."

Most insurance companies will replace masks a few times each year, and accessories like nasal cushions more frequently. Some CPAP users like to keep two or three masks they're comfortable with, so they can switch occasionally to relieve pressure and irritation on the face.

Bells and whistles
Depending on your lifestyle and personal preferences, you may find spending a little extra money on special features such as battery backup to be worthwhile.

If you use a humidifier in a cold room, a rainout reduction kit can help prevent condensation from forming in the hose. You can even buy hose extensions (to improve your mobility) and insulated sleeves (to give them a softer look and feel).

Many CPAP models contain a memory chip that helps your doctor measure your compliance; others adjust pressure automatically when you travel to higher altitudes. Browse online retailers and talk with your medical supplier about what options might make CPAP therapy more effective.

Alternatives to CPAP
Sometimes even the best CPAP machine and mask still won't help, if you're too sensitive to the level of air blowing through the hose. In these cases you may need to try a more sophisticated machine, such as a BiPAP or an APAP.