I have used colloidal silver (not gel) successfully for my family members' eye issues, as well as my pet's eyes issues for years. If you use it, make it a higher ppm like 30 or 40, and spray it on rather than drop it in. This way she can easily do it herself and it will not only cover the outside but get in the eye too. Once is not enough; you need to keep it up for about 3-4 days, about 3-4 times a day. If it's an a pathogen, it should be better within that time.