Devices, systems, and methods for medication infusion are described herein. In some embodiments, a system includes a patient access subassembly, a first fluid reservoir, a second fluid reservoir, and an assembly. The assembly can have a first configuration in which the patient access subassembly is in fluid communication with the first fluid reservoir via a first tube, a second configuration in which the first fluid reservoir is in fluid communication with the second fluid reservoir, and a third configuration in which the first fluid reservoir is in fluid communication with the patient access subassembly via a second tube, the first fluid reservoir fluidically isolated from the first tube in the third configuration.