Refrigerant cartridges for cryotherapeutic neuromodulation and associated systems and methods are disclosed herein. In one embodiment, for example, a cryotherapeutic system includes a shaft having a proximal portion, a distal portion and a supply lumen along at least a portion of the shaft. The shaft can be configured to locate the distal portion intravascularly at a treatment site. The supply lumen can be configured to receive a refrigerant from a refrigerant cartridge. The refrigerant in the refrigerant cartridge can have a moisture concentration of at most 10 ppm. The system can further include a cooling assembly at the distal portion of the shaft that has an expansion chamber in fluid communication with the supply lumen.
