Thanks for providing more information.
I would recommend you to get an evaluation by ENT specialist /dentist for a clinical exam including your throat exam and the inner palate and walls of the oral cavity as your description and symptoms are raising a suspicion of herpetic lesion.
You need to undergo blood test-HSV1 IgG & IgM,Sore culture to rule out Herpes.
Prednisone is steroid and helps in reducing inflammation.
Ciprofloxacin is antibiotic treating for bacterial infection.
Sweet taste in mouth may occur from mouth conditions like stomatitis or inflammation of mouth,gingivitis or inflammation of gum ,glossitis,medications induced,reflux of acid from stomach,any respiratory tract infection,sinusitis or post nasal drip,electrolyte imbalance etc.
Dry mouth can also be a factor.
If your symptoms'll persist even after taking complete course of prednisone and Ciprofloxacin then make an appointment with ENT specialist.
Hope this helps.
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