Can You Get a Cough From CPAP?

Key Takeaways

• A cough caused by CPAP is rare and instead, is usually caused by conditions like sinus and upper respiratory infections, allergies, acid reflux, and asthma.
• Research suggests that well-maintained equipment isn’t the direct cause of sinus or upper respiratory infections, however, sometimes CPAP use can worsen symptoms like cough from other causes.
• Using humidified air, preventing water from collecting in CPAP tubing, cleaning dirty equipment, and using a well-fitting mask can make CPAP use more pleasant, safe, and easier to stick with.

Reasons Why CPAP Can Make You Cough

There are multiple potential reasons a person could develop a cough when using a CPAP machine, often from dry CPAP air, unclean equipment, and poor mask fit. A person may think they have a cough from CPAP when it actually stems from a different cause, like allergies or an infection. Below we explore the connection between common CPAP pitfalls and coughing.

Dry Air or High-Pressure Air

When CPAP therapy delivers dry air, it may cause a dry nose, mouth, or throat, as well as a stuffy nose, in some sleepers. The CPAP machine’s pressure settings, changes in air pressure during the night, or a lack of humidification may also lead to feelings of dryness after CPAP therapy.

For some people, CPAP-related dryness may be more than a minor irritation and result in discomfort, a sore throat, or a cough. Using a CPAP machine with heated humidification may reduce dryness, along with any related symptoms. 

Excess Water or "Rainout"

While dryness appears to be a more common side effect of CPAP usage, some sleepers experience the opposite problem, called "rainout." Rainout is condensation that occurs when excess water from humidification gathers in the CPAP mask or tubing. Anecdotally, some sleepers have reported that this excess water enters the airway, prompting a cough.

Adjusting the humidification settings could reduce rainout, as well as any problems it may be causing. Other potential solutions include a tube jacket, which keeps tubing warm so humidified air won't cool off and become water, or heated tubing.

Poor Mask Fit

A CPAP mask leak not only compromises the quality of CPAP therapy, but can also worsen dryness and irritate the upper airway, which may result in a cough. According to one CPAP manufacturer's study, 45% of people who quit using their CPAP machine do so because of a mask leak.

To correct a poor mask fit, you can try adjusting the straps of your mask and headgear at home, so it's neither too tight nor too loose. If that doesn't help, talk with your doctor. They can identify if you might benefit from a different mask size or another type of mask altogether.

Dirty CPAP Equipment

Because CPAP therapy delivers air through tubing and a mask all night, night after night, it’s important to keep the equipment clean. While the lungs and airways are generally good at filtering out bacteria and mold, regularly cleaning CPAP components helps reduce unnecessary exposure, especially over long-term use. 

In rare cases, bacteria or mold can build up in CPAP masks, tubing, or humidifier chambers if they aren’t cleaned or dried properly. This may be more of a concern for people with underlying lung disease, those who smoke, or individuals with weakened immune systems. 

People worried about catching a cough from their CPAP machine may be tempted to use harsh cleansers, but manufacturers don’t recommend this. Cleansers containing alcohol, bleach, essential oils, scents, or antibacterial agents may leave a residue that's harmful when breathed in. CPAP cleaning machines, like ozone or UV light cleaners, may also cause harm and potentially damage your machine.

Always follow the manufacturer’s cleaning guidelines and replacement schedule to help keep CPAP therapy safe and comfortable. Usually, that means cleaning your equpiment with a mixture of water and either mild soap or distilled vinegar.

Allergies or Sensitivities

Allergies and sensitivities are more common among people with obstructive sleep apnea, and can cause symptoms including a cough. Allergies can worsen at night for multiple reasons, such as mucus moving in the nasal passages after lying down, natural nighttime fluctuations in histamine levels, and increased exposure to dust mites or pet dander in the bedroom. CPAP users may incorrectly attribute an increase in nighttime allergy symptoms to CPAP therapy.

In very rare cases, a person may be allergic to components of their CPAP mask, such as silicone. An allergy or sensitivity to CPAP mask components would most likely cause skin irritation or an itchy rash. The solution to this problem would be trying out masks that contain different materials and ultimately choosing one that doesn't cause an allergic reaction.

Underlying Respiratory Condition

Oftentimes, a person's cough stems from an underlying respiratory infection or condition, like bronchitis, pneumonia, or chronic obstructive pulmonary disorder (COPD). While these issues are unlikely to be caused by CPAP therapy, they may be exacerbated by it, especially if CPAP equipment is dirty, the air isn't properly heated or humidified, or a CPAP mask doesn't fit appropriately.

A doctor can help you identify the underlying cause of your cough. Coughing is an important function that the body uses to fight infections and clear the airway of mucus, so health experts advise using cough suppressants sparingly, especially before the cause is known.

Taking cough suppressants at night to facilitate sleep is a common recommendation. It's very common for coughs to dissipate on their own over time, however, identifying the underlying cause for the cough will determine the best treatment plan.

What to Do if You Have a Cough While on CPAP

If you use a CPAP machine and have a cough, talk to your doctor to help find the cause and determine the best possible treatment. Consider trying the following to reduce airway irritation and improve hygiene:

• Add a heated humidifier to your CPAP therapy to counteract dry air.
• Adjust heated humidification settings, or ask a doctor to do so, if you see excessive water in CPAP tubing.
• Adjust your CPAP mask, or ask your doctor about trying different masks if yours is ill-fitting or an air leak is present.
• Clean your CPAP accessories using water with gentle soap or distilled vinegar based on your equipment’s manufacturer schedule.
• Replace your CPAP accessories, including the mask, tubing, filter, and water chamber, according to the manufacturer’s schedule.
• Dump old water out of the water chamber before refilling it with clean water.
• Only use distilled water in your water chamber, not tap water or bottled water.

When to See a Doctor

According to the American Lung Association, an occasional cough is common, normal, and often dissipates on its own. While every person's situation varies, the following are examples of symptoms that should prompt you to see your doctor if occurring with the cough:

• Shortness of breath
• Chest pain
• Leg swelling
• Large amounts of blood in the mucus
• Excessive mucus or phlegm
• Fever for more than 48 hours
• Persistent fatigue (weeks)
• Night sweats
• Unintentional weight loss

If you develop a cough and suffer from the following medical conditions it would be be wise to see your doctor: 

• Lung disease (asthma, COPD, emphysema)
• Heart failure
• Cancer
• Suppressed immune system
• Kidney or liver disease
• Acid reflux
• Smoking for many years

Seek immediate medical attention for a cough that's associated with severe wheezing, a barking sound, chest pain or trouble breathing.

It's also a good idea to see your sleep specialist or doctor if you're having trouble with your CPAP therapy. If you think you’re experiencing CPAP side effects, whether coughing or something else, your healthcare professional can work with you to troubleshoot the problem and ensure you’ll be able to continue your CPAP therapy.

Frequently Asked Questions

Should I use CPAP with a cough?

Whether or not you should use a CPAP with a cough depends on the underlying cause of your cough and the state of your CPAP machine. Multiple research studies have found that CPAP therapy can help relieve the chronic cough often associated with obstructive sleep apnea. 

CPAP manufacturers and expert medical groups like the American Thoracic Society alike recommend continuing CPAP therapy when having upper respiratory symptoms caused by viruses (like a cold or COVID-19) like a runny nose, post nasal drip or cough.

However, if you feel severely ill or like you cannot breathe while using your CPAP machine, talk to your doctor about whether you should temporarily stop CPAP therapy. If you think an unclean CPAP machine or ill-fitting mask is causing or worsening your cough, talk to your doctor and ask if you should continue using your machine or take a break until these issues are fixed.

Can sleep apnea cause coughing?

Research has found that a high percentage of people with a chronic cough also have obstructive sleep apnea, and OSA may contribute to issues with coughing. That said, OSA might not be fully responsible for chronic coughing. A third disorder related to both sleep apnea and chronic coughing could be to blame, such as gastroesophageal reflux disease (GERD) or cough-variant asthma. 

Can CPAP cause a sinus infection?

General consensus in the medical community is that CPAP therapy isn't linked to an increase in sinus or upper respiratory infections. In theory, however, if your CPAP machine or the water in your CPAP's water tank is dirty, it's possible that contamination could cause or exacerbate an infection. Be sure to clean and replace your CPAP supplies on the schedule provided by your CPAP manufacturer.