Brief Answer:
Information on xerostomia

Detailed Answer:
Hello and welcome,

There are a few fairly common causes for this:

1. Your mouth is open at times while you sleep. This can be from allergies, a stuffy nose, snoring or even sleep apnea. If the mouth is open it can get more dried out.

2. Many medications (both over the counter and prescription) can cause a dry mouth which may not be noticeable until you sleep during which time your salivary glands make less saliva. Some herbal teas can be drying too.

3. Inadequate intake of water before going to bed.

4. Stress can interfere with saliva production.

5. Caffeine, soda pop, and especially tobacco and alcohol can cause night time dry mouth. Alcohol is well known to have a dehydrating effect.

Now for a less common cause:
Sjogren's is an autoimmune disorder that can cause dry eyes and mouth. But people tend to find it a problem thoughout the day, not just at night.

I hope this information helps. Please let me know if I can provide further information.

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