The Prep-Lock tamper evident additive port cap from IMI adds protection to the add port of IV bags from various manufacturers. With a one-click installation, the cap aims to provide protocol assurance and tamper-evident protection that extends USP <797> guidelines beyond the pharmacy to the patient. The cap is designed to be cost effective and to reduce the risk of contamination by providing a physical barrier to diversion and misuse, increasing safety for health care providers and patients.