A portable, electronic, thermal-insulating device designed to contain an autoinjector (e.g., insulin pen), or other portable medication vial, in order to maintain its contents within a specific temperature range while being carried by the patient. It is in the form of a small cylinder, which may also function as a cap for the autoinjector, and is made of thermal-insulating materials, typically a phase change material (PCM). Its electronics enable functions related to indication of medication temperature, administration scheduling/events, and/or wireless connectivity. This is a reusable device.