Hiya and welcome to the forum. Ask your vet for antibiotics that can be given straight into the mouth with a syringe. If you put it in the food you don't know if he is getting the full amount.
Ear infections can be serious, however with the right antibiotics he should be fine.
Common antibiotics are Baytril (Enrofloxacin) and Septrin (Trimethoprim Supla) what ones is he on?
Is he eating? If not you will need to syringe critical care which is avaliable from the vet in powdered form and has all the nutrients in for small animals. This needs to be done every 2 hours, wrap in a blanket with pigs back to your stomach and feed with a syringe also available from your vet.
As you know pigs don't make their own vitamin c up so if he is not eating then you will need to get some vitamin c drops down him. Again in the syringe and not put in the water bottle. I would also syringe water throughout the day to keep him hydrated.
I hope that helps a little, I know it is worrying.
Good luck!
Louise
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