Brief Answer:
Investigations, Antibiotics, metronidazole...

Detailed Answer:
Hi.
Bad breath is called Foetor in medical language. You have a history of blockage of nose due to built-up that there is problem even in breathing.
This can be due to atrophic rhinitis as can be easily diagnosed by an ENT Surgeon on endoscopy; if this is so you may need an active treatment and nasal washes.
This can be Due to Chronic Sinusitis, the sinus can have pus which gives you the symptoms.
I would advise you to have a consultation with an ENT Surgeon, get Clinical examination done; CT scan of the Sinuses and an X-ray of the chest is mandatory.
Get the treatment according to the reports.

The Dry mouth is called Xerostomia. It has many causes. Commonest is due to sub-clinical infection of the mucosal glands, not allowing the secretions and hence there is dryness. A course of proper antibiotics and metronidazole may sometimes helps to alleviate the problem. You have to avoid oral decongestant tablets for cough and cold as they too can cause dryness.
If the CT Scan is normal a course of steroids orally can help in dryness. Avoid too hot and too cold foods and beverages, No foods which are dry as they abrade the mucosa more. Take plenty of oral fluids as dehydration adds to this problem.

Also take therapeutic dosage of Vitamin A and D and continue as multivitamins with anti-oxidants.

I hope this helps you as it helps many of my patients.
Please feel free to ask for more if you need to and you may please rate this answer.
Wishing you an early recovery.
Dr T Chandrakant
ENT and General Surgeon

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Brief Answer:
Not really

Detailed Answer:
Please consult an ENT Specialist. Rheumatology Doctor may not be in a position for helping you, unless you have associated problems.

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