Box turtles are great pets with real character but they are not the easiest turtles to care for in comparision to other turtles who are much easier to look after. Although I must say all turtles need a certain level of maintenance. When taking on the responsibility of caring for a turtle you will inevitably come up against some health issues, one of them might be a box turtle eye infection
If your turtle is showing signs of an eye infection, its a good idea to look for other symptoms such as wheezing or gasping, a runny nose and breathing through their mouths. If a number of these symptoms have been spotted then the signs are pointing at your turtle having a respiratory infection and you will need to take it to see a vet as soon as.
If your box turtle has swollen eyes they may be having an allergic reaction to the substrate that you are using in their enclosure. Some turtles are allergic to earthly substrates and will have swelling around the eyes as a result of their allergy towards this sort of bedding. If your using earth or soil based bedding then try replacing the bedding with another and monitoring your turtle for a week or so to see if the swelling goes down. If the swelling still persists then you will know that your turtle does not have allergy problems and it could be because they are lacking vitamin A in their diet.
Vitamin A deficiency can be a cause of swelling in the eyes of box turtles and a way you can treat this is to make sure you are introducing foods that are high in vitamin A as a part of your box turtles diet every time you feed them. Foods such as Collard greens, carrots, kale and parsley all contain a good amount of vitamin A and can be added to each meal to help fight against this problem.
If nothing changes and the problems your box turtle is having remains then its time to see a vet. A vitamin injection might be necessary to help restore your turtles health and fix their turtle eye infection altogether.