There is more than one dose worth of epinephrine in each EpiPen device.
This is true...only one-fourth of the epinephrine in an EpiPen auto-injector is released with the injection.
But don’t run out and tell everyone they can reuse their EpiPen. The extra epinephrine in the cartridge is overfill to ensure that the release mechanism works properly.
Patients can’t get to the overfill epinephrine without dismantling the device and taking out the cartridge...which can be dangerous.