The average dose for tobramycin ophthalmic solution for both children and adults is one drop in each eye every four hours for mild infections, according to Mayo Clinic. For severe infections, individuals should use one drop in each eye every hour.
It is important to note that these dosing instructions are just averages and should not replace those received from a doctor, Mayo Clinic states. Dosing can vary from the average for a number of reasons, including the strength of the medicine, the number of total doses per day and the length of time the eye drops are used. Individuals should always follow the dosing instructions given by their doctors.