Let me at the outset tell you that it is unlikely to be anything serious.
Though it is not serious but as you can understand it needs investigations to ascertain the cause and treatment.
Following are the possibilities and related investigations;
1) Sinusitis; will require an MRI of sinuses.
2) Pharyngeal diverticulum; barium esophagogram would be needed to establish it.
3) Acid reflux/GERD and esophagitis; Need upper GI endoscopy.
4) Chronic laryngitis; need indirect and direct laryngoscopy.
Environmental pollutants and toxic products found in workplaces can cause chronic laryngitis. Infectious and allergic laryngitis is identified by following investigations;
a) MRI of larynx
b) Skin allergy test
c) Serologic markers for autoimmune disorders/ autoimmune panel.
d) Swab of the larynx, culture and sensitivities for bacteria, fungi, and viruses.
e) Sputum culture.
Chronic laryngitis is treated by;
2) Anti allergic
3) Avoidance of fat, alcohol, and caffeine (if one does)
4) Avoid tobacco or smoking (if you do)
5) Avoid environment pollutants and irritants.
6) Steam inhalation
7) Room humidifier
8) Drinking plenty of liquids (2-3 liters a day).
Reflux laryngitis and Acid reflux / Gastroesophageal reflux disease (GERD); treatment is by avoidance of reflux-inducing foods (fatty foods, chocolate), eating five small meals a day without snacking, avoidance of meals for two to three hours before lying down (except for medications), elevation of the head of the bed and an H2 antagonist or a proton pump inhibitor.
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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