Based on the discovery that MBLAC1 is a specific, high-affinity target for Ceftriaxone (Cef), MBLAC1 may be used for identifying treatments for addiction to substances of abuse. Methods for identifying therapeutic agents for treatment of addiction to a substance of abuse include using an assay to determine if a test agent is capable of binding to MBLAC1 or disrupting binding between MBLAC1 protein and Cef, and identifying such a test agent as a candidate therapeutic agent for treatment of addiction to a substance of abuse. MBLAC knock-out (KO) animals, methods of use thereof, and kits are used for identifying a therapeutic agent that reduces the actions of at least one substance of abuse. Methods also include using cellular extracts from tissue or cultured cells taken from wild-type (WT) MBLAC1 and MBLAC1 KO animals for screening for novel, Cef-like molecules in vitro, and using cells from a MBLAC1 KO animal to test for Cef-like actions of a test molecule.