A male-disinfecting cap is configured to couple with and apply an antiseptic agent to medical male luer-lock connector of the type including a post having a lumen. The cap includes a receiving portion which defines a chamber. The post of the male luer-lock connector is received into a single opening of the chamber. The receiving portion is configured to fit within the skirt of the male luer-lock connector when the post is received into the receiving portion. At least one vent is defined on the internal surface of the receiving portion and extends from the opening into the chamber, where an antiseptic is disposed. Protrusions on the external surface of the receiving portion engage helical threads of the internally helically threaded skirt. The male-disinfecting cap also includes a seal that prevents evaporation of the antiseptic agent in the chamber prior to use.
