I think 喉嚨發炎應該食抗生素 if you want your child to be recovered sooner. When young child has 喉嚨發炎it can turn out very badly if it's not treated carefully. If your child finishes 1 whole course of antibiotic, it should be fine.
Ask your doctor in what circumstances that he will give your child antibiotic. If you don't trust your doctor, change to consult another one.
It's very uncomfortable and painful when 喉嚨發炎 together with fever, even adults will take antibiotic lar.
My doctor told me that my daughter's 喉嚨發炎 is not caused by 病毒, it's 細菌引起的炎症. Therefore, he quite insists in giving antibiotic to my daughter.
Anyway, consult the doctor further if you have any query. If you don't agree to his treatment, consult another doctor. Only doctors and professionals know what is best for the patient.