A quick-connect coupling is provided for use in a medication infusion system, to permit temporary disconnection and subsequent re-connection of a medication infusion pump relative to a patient without requiring removal of a transcutaneous infusion cannula. The coupling is mounted in-line with a length of infusion tubing and includes a female component with a needle recessed therein and adapted for slide-fit connection with a male component having a self-sealing septum. Radial tabs on the male component slide freely into longitudinally open slots formed in the female component, whereupon the male component is rotatable to displace the tabs with interference fit past undercut cam surfaces into alignment with radially open ports formed in the female component. When connected, the male and female components are effectively locked against longitudinal separation. However, the male and female components can be separated safely and easily, and without applying substantial longitudinal forces, by rotating the male component to displace the tabs back to alignment with the longitudinally open slots in the female component.