Abstract: Provided are compositions comprising an opiate analgesic and an active compound containing the R isomer of N-methylnalorphine in a pharmaceutically acceptable carrier. Also provided are methods of treating opiate intolerance by administration of an active compound containing R N-methylnalorphine or a pharmaceutically acceptable salt thereof. The active compound may administered either acutely or chronically to subjects receiving opiate treatment. Further provided are methods of inducing analgesia by administering to a subject an opiate analgesic concurrently with an active compound containing R N-methylnalorphine or a pharmaceutically acceptable salt thereof.