When you blink, your upper lid goes up and down….Your lower lid moves side to side and creates a vacuum within the lower punctum to take tears/fluid off the surface of the eye thereby decreasing the effect of the eyedrops that are being applied, for they are then washed away. To keep the pharma drops on the surface of the eye for better absorption I tell my patients to put the drop in and then simply close the eye for a full minute (longer is fine) to keep the punctal openings opposed and thereby keep the medication on the eye for better effect. Attempting to find the exact spot for pressure on the nasolacrimal system can be difficult.