How anxiety causes dry mouth
The information below is interesting because anxiety can actually make it seem like you have Sjogren's syndrome. In addition, anxiety can also cause burning mouth/lips which I wonder if involves inflammation in that area.
"Generally, there are several issues that lead to this dry mouth feeling from anxiety, and any or all of them may relate to your dry mouth. These include:
Mouth Breathing
Air has a tendency to dry out the mouth, and those with anxiety are tremendously prone to mouth breathing. Often this type of breathing is the response to severe anxiety symptoms, like those that occur during an anxiety attack. Mouth breathing can be irritating to the saliva, and may dry out your tongue in a way that feels like dry mouth is occurring.
Acid Backup
Those with acid reflux problems may also be more prone to dry mouth. This is because during periods of intense anxiety, the body is more prone to acid reflux, and acid can affect the salivary glands and lead to less saliva and the feeling of a dry mouth. It may also lead to a sticky feeling and bad taste, both of which are considered dry mouth related.
Fluid Changes
In some cases, the issue may be with the way your body moves around fluid when you're experiencing severe anxiety. When your fight or fight system is activated, your body make take fluids - like saliva and water - and move them to the areas they feel need them more. That may dry out your mouth as well.
Dehydration
Of course, some dry mouth may genuinely be because you have a dry mouth. Those that aren't drinking enough water are more prone to severe anxiety symptoms. Beyond that, those with anxiety are more likely to notice unusual physical sensations, meaning that if you have anxiety you're more likely to notice that your mouth is dry then when you don't."