I was told to gargle with Kaopectate mixed with Benadryl. Mix 4 oz of cherry benadryl (relieves scratchy throat) with 4 oz of cherry Kaopectate (coats the throat stops the burn). Then just gargle swish it in around in your throat. Can swallow it if you want to.
The infection may have now spread to your larynx (voice box).
This may be part of the bacterial infection or a viral problem. If it is a viral problem the antibiotics will not help.
The best thing is to drink plenty of warm drinks (avoid milk) and take pain relief and suck on throat lozengers.
Do NOT speak. Trying to speak can damage the vocal chords beyond repair. Use paper and pen and write any messages rather than trying to force a voice. If you have a cough, do this as gently as possible. Do not even whisper. I was 17 when this first happened to me and the doctor gave me the advice I am giving to you now. I had to look after my voice because I loved singing. Although I did sing in public, I didn't become a professional singer.
When the larynx is ill, it needs complete rest to recover. If you keep trying to use the voice by force or shouting or even whispering, the damage to the vocal chords can get to the point that you could end up having vocal nodules and the voice not return to normal.
You may know of some pop singers who have very croaky voices. Bonny Tyler is one, can't remember the name of the bloke singer.
So, mummmmms the "word".
Best wishes. :)