I have gone through your question.It seems your son is having allergy
in the eye.Doctor has prescribed correct medicines. I would suggest you to go give it for 3 days, if after that no improvement then you can try these medicines Keto eye drops 2 drops 3 times day for 5 days and Oflox
eye drops 2 drops 3 times a day. when you start these medicines u should stop the earlier medicines.
hope it helps