Brief Answer: Can be due to many causes. Detailed Answer: Hello, Thanks for trusting us with your health concern. I have seen all the reports attached with the query. The symptoms that you are feeling could be related to a recent increase in the synthyroid doses. The weakness and fatigue could be related to decreased vitamin D 3 levels. Other possible causes include anxiety, dehydration due to poor fluid intake, breathing through the mouth excessively, intake of alcoholic beverages, simply as a natural result of aging or smoking. Some remedies to minimize your discomfort includes- 1.Sucking on sugar-free candy or chewing sugar-free gum 2.Drinking plenty of water to help keep your mouth moist. 3. Protecting your teeth by brushing with a fluoride toothpaste, using a fluoride rinse, and visiting your dentist regularly 4. Breathing through your nose, not your mouth, as much as possible 5. Using a room vaporizer to add moisture to the bedroom air 6. Using an over-the-counter artificial saliva substitute. Please feel free to discuss further. I will be glad to answer the follow up queries that you have. Wishing you good health. Regards. Dr. Rakhi Tayal.

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