Tobrasys is an antibiotic eye ointment containing Tobramycin, which belongs to the aminoglycoside class. It is primarily used to treat external bacterial infections of the eye and its surrounding structures, such as conjunctivitis (pink eye) or blepharitis. It works by stopping the growth of bacteria that cause infection. Because it is an ointment, it stays in contact with the eye surface longer than drops, making it effective for nighttime use. It is important to complete the full course as prescribed by a doctor to prevent the infection from returning. It should not be used for viral or fungal eye infections.