I am Dr. Arun and will be helping you today.
One of the most common causes for your symptoms are;
1) Sinus infection termed sinusitis.
2) Rhinitis; nasal inflammation which is commonly due to allergies.
But tooth or gum infections, ulcers in mouth or tongue too may give these symptoms, as had been suggested to you.
If none of these are identified, you need to be investigated for;
3) Deficiency of B12
4) Salivary gland inflammation.
You may need following investigations;
1) Electromyography/nerve conduction studies (EMG/NCS)
2) MRI of the spine and brain
3) blood glucose, glucose tolerance test and glycosylated hemoglobin
4) serum B12 level with methylmalonic acid (with or without homocysteine),
5) serum protein electrophoresis
6) Anti-nuclear antibody
7) Lyme testing
8) Rheumatoid factor
9) Sjogren's syndrome testing (Anti-Ro, Anti-La Antibodies)
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
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