Hello and Welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice. As per your query you have symptoms of sore throat with mouth ulcers,muscle aches and dry lips which is due to bacterial infection and due to dry mouth i.e xerostomia. Need not to worry. I would suggest you to maintain complete hygiene and apply numbing gel on ulcers, lips and you can use Lidocaine patches if pain is there. You should take plenty of fluids and avoid fried food. You should try to breath from nose instead of mouth. Consult ENT physician once so that physician can take complete history and check other symptoms to find what exactly causing your symptoms. Doctor may prescribe proper course of antibiotics along with anti-inflammatory medications. You should use saliva substitute as it will enhance secretions of saliva. You should chew sugar free gum. Hope I have answered your query. Let me know if I can assist you further.