Inflation devices for inflating intragastric devices and associated systems and methods are disclosed herein. In several embodiments, an inflation device can include a tube, an inner detent, and an outer detent. The tube can extend from a proximal portion of the inflation device to a distal portion of the inflation device, and can include a handle at the proximal portion and a barb at the distal portion. The barb can have a cross-sectional dimension greater than a cross-sectional dimension of a corresponding inflation port of an intragastric device. The inner detent can be positioned over the barb and can include a mating interface. The outer detent can be positioned over the inner detent, and can be configured to attach over a proximal cap of the intragastric device. The tube can be longitudinally advanceable relative to at least one of the inner and outer detents,