For eye infections I've always used Terramycin Opthalmic ointment, available at most drug stores without a prescription. You may have to ask the pharmacist for it though.
A little dab placed on the eye 2 times a day may take care of it. If not you definitely need to get to a vet.
Some suggestions on your setup. Pacman frogs like to be able to burrow down in moist bedding. The gravel will not allow him to do this. You might want to switch that out for coco fiber bedding. One name brand for this is Bed A Beast. It comes in little pucks of bricks and you have to soak it in hot water to soften it. I would suggest a good 2" deep and keep it moist but not soaking wet. Provide a shallow water dish for when he wants to really soak. A water dish is much easier to keep clean than having half your tank as a pool.
Aquarium gravel could also lead to impaction if he should swallow any while eating.
Hope this helps.
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BigT
There is a difference between ignorance and stupidity. The ignorant can be taught, stupidity is beyond our control.
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