Methods and compositions of treating a subject for cancer pain are provided. In the subject methods, a subject is treated for cancer pain by administering to the subject an effective amount of a narcotic emulsion, e.g., fentanyl elmulsion, formulation. In certain embodiments, the emulsion formulations include a narcotic active agent, oil, water and a surfactant. Also provided are methods of making the subject emulsion formulations as well as kits that include the emulsion formulations.