How to use Genoptic ophthalmic. This medication is used to treat bacterial infections (such as blepharitis, conjunctivitis) of the eye and the skin around the eyes (such as eyelids). It is also used to prevent infection after eye injury or surgery.It belongs to a class of drugs known as aminoglycoside antibiotics.his medication is used to treat bacterial infections (such as blepharitis, conjunctivitis) of the eye and the skin around the eyes (such as eyelids). It is also used to prevent infection after eye injury or surgery.