DRUG INJECTION DEVICE

The present invention relates to a pharmaceutical injection device, comprising: a main body case having a pharmaceutical syringe attachment component on its distal end side; a distal end cap that can be removably attached to the dista! end side of the main body case; a first driver that moves a pharmaceutical syringe unit attached to the pharmaceutical syringe attachment component to the distal end side or the rear side; a second driver that moves a gasket of a pharmaceutical syringe constituting the pharmaceutical syringe unit to the distal end side; an attached state detector that detects the attached state of the distal end cap to the main body case; and a controller that, during pharmaceutical injection, can execute a normal pharmaceutical injection mode in which the first and second drivers are actuated when the attached state detector has detected a state in which the distal end cap has been attached to the main body case , and can execute a simple pharmaceutical injection mode in which only the second driver is actuated when the attached state detector has detected a state in which the distal end cap has not been attached to the main body case.