A sterilization cap carried on a needle support end of a syringe. The cap includes a main body having first and second ends, the first end being connectable to the needle support end, as well as being connectable onto the needle support end alone of a primary or IV extension line. A sponge secured within a sponge cavity within the second end is saturated with a sterilizing liquid. A removable cover attached to the second sealingly encloses the sponge until the syringe is used. The second end is sized, when the cover is removed, to fit over a clave tip of a clave extension or IV tubing a distance sufficient to compress the sponge to sterilize the clave tip with sterilizing liquid expressed from the sponge.