Sleeping with your mouth open at night can most certainly cause it to be dry in the morning. The dryness can contribute to the fuzzy-feeling tongue and bad breath that typically accompany "morning mouth," which is one reason that many people like to brush their teeth before interacting with others in the morning. Of course, sleeping with your mouth open may not be the only cause of morning dry mouth. Once you find the cause, you can look for an effective solution.
If you tend to sleep with your mouth open, you may wake up to a mouth that feels like the Sahara Desert. The term for this is xerostomia. Along with your mouth feeling bone dry, you may also notice that your throat feels a bit sore from the lack of moisture. Your mouth may feel sticky, and your tongue may appear red and raw. Even your teeth may feel dry. You may also notice that you have chapped lips. It is likely that you'll have bad breath as well.
Besides causing bad breath, dry mouth can also increase your risk for gum disease, as the lack of saliva allows bacteria to adhere to teeth and gums, rather than being washed away. For the same reason, a dry mouth can also cause you to get cavities. A dry mouth may also increase your risk for fungal infections in your mouth, according to MayoClinic.com.
One way to prevent a dry mouth caused by sleeping with your mouth open is to look at the reason you are sleeping with your mouth open in the first place. You may be congested or are having episodes of sleep apnea. If you suspect sleep apnea, see your doctor, as the symptoms of this disorder can be much more serious than a dry mouth. You may also have sinus abnormalities that cause you to breath with your mouth open. Your doctor will be able to identify any such abnormalities, if this is the case.
You can also get a dry mouth from taking certain medicines. Antihistamines and antidepressants are two medicines that are well-known for having this side effect. It may be that they are exacerbating your problem with morning dry mouth. Dehydration is another cause of dry mouth.
Diseases such as diabetes and anemia may also contribute to a dry mouth.
If you are congested, visit your doctor. She may recommend a nasal decongestant or nasal steroid that allows you to breathe freely during the night. You can also put an additional pillow under your head while you sleep. This may help to reduce congestion and help you to sleep with your mouth closed. If you suspect that you may be slightly dehydrated, increase the amount of water you drink during the day.
If you have tried all preventive measures and still have a dry mouth in the morning, there are some things you can do to help. Keep a package of saltines and a glass of water on your bedside table. When you wake up, take a drink and eat a saltine. The salt in the cracker will stimulate the production of saliva in your mouth, helping to alleviate the symptoms of dry mouth. Brushing your teeth immediately upon waking will have a similar effect and will remove the bad breath caused by a dry mouth.