It looks like your doctor is suspecting an allergic reaction
rather than an infection. Lotepred and ocupol D are good drugs but need to be used with caution.
What is the dosage in which he is using them? Also what has been the response to the treatment? What type of tapering schedule has your doctor prescribed for him?
There are multiple factors that need to be considered here. I would suggest that u see a cornea
specialist in your area if you are not getting relief with the treatment being followed.
Also pls remember that this type of disease needs long term treatment and would need considerable patience and perseverance from you.
Hope this helps and yu r son gets better soon.