Sleep apnea, a disorder that involves abnormal breathing during sleep, is a difficult condition to detect. The afflicted individual generally has no knowledge of the breathing pauses or low breathing episodes that are used to diagnose the disease. What the sleep apneic might experience, however, is chronic fatigue and, possibly, the sensation of a very dry mouth and throat upon waking.
The dryness usually results from open-mouth sleeping, which is common among individuals suffering from obstructive sleep apnea or OSA. The breathing pauses that characterize OSA result from relaxation of the muscles that keep the airway open; it is possible that a similar relaxation of the facial muscles may cause the individual’s mouth to open as she sleeps. Or, the open-mouth sleeping could be just habitual.
Other signs of OSA include snoring, frequent waking at night, and decreased ability to concentrate—a by-product of fatigue. Individuals experiencing these symptoms should talk to their physician. A true diagnosis of sleep apnea does require participation in a sleep test.
Sleep apnea leads to lower levels of blood oxygen, which wakes the afflicted individual and robs her of restorative sleep. In some cases, the condition is serious enough to require surgery to increase the posterior airway space.
CPAP-induced dry mouth
Surgery, however, is not the first choice of treatment. The safer and more common course of action is CPAP therapy. A CPAP is a ventilation device that uses forced air pressure to keep the individual’s airway open at night. The air pressure is delivered through a full-face mask, nasal mask, or nasal pillows. Dry mouth is a routine side effect of CPAP usage, particularly among inexperienced CPAP users. The symptoms can be uncomfortable enough to cause some patients to discontinue therapy.
For those using nasal masks or nasal pillows, dry mouth can be a sign of open-mouth sleeping. This should be addressed immediately, because an open mouth limits the effectiveness of the CPAP. If air is leaking out the mouth, the device cannot effectively hold the airway open. Strategies to address open-mouth sleeping include using a flexible chin strap that gently holds the mouth shut, or switching to a full-face mask. The full-face mask covers both mouth and nose.
Individuals already using a full-face mask may suffer from dry mouth due to the pressurized air flow. In this case, the first remedy is to try using a heated humidifier that attaches to the CPAP. These patients should also check the fitting of the mask and quality of the mask’s seal. Other strategies include:
- Keeping a glass of water nearby to quench thirst during waking episodes
- Using a saline nasal spray before bedtime
- Using of an over-the-counter, dry mouth remedy such as Orazyme
- Sleeping on one’s side, rather than on one’s back
Many CPAP users have reported an improvement in dry mouth symptoms over time and through continued use of the ventilator.