What is the purpose of pressure to the inner canthus after administering eye drops?

The purpose of applying pressure to the inner canthus after administering eye drops is to prevent tears from washing away the medication. When eye drops are administered, they can easily be drained away through the tear duct, which is located at the inner corner of the eye. By applying gentle pressure to this area, the flow of tears can be temporarily restricted, allowing the medication to remain in contact with the eye surface for a longer duration. This technique enhances the effectiveness of the medication by ensuring it has adequate time to be absorbed and exert its therapeutic effects. Therefore, the application of pressure aids in maximizing the efficacy of the eye drops by minimizing their clearance through the tear drainage system.