Abstract: A cap sanitizer with an anti-bacterial sponge therein for sanitizing a dispenser bottle tip or other similar device. The inner side portions of the cap are lined with a continuous sponge (or absorbent foam) ring soaked with antibacterial solution. An o-ring is disposed below the sponge to prevent solution from leaking from the dispenser bottle when the cap is in place. A cavity within the dispenser cap serves as a reservoir for the antibacterial solution, which is slowly channeled to the sponge ring via a perforated separating film. Alternatively, the reservoir may be disposed between the sponge and the sides of the dispenser cap sanitizer, with a perforated separating film between the sponge and the antibacterial solution. Solution from the reservoir is channeled through the perforated separating film into the sponge. In an alternative, a sanitizer cap for a toothbrush is provided having stiff fibers extending through the perforated membrane.