Auto injector with temperature control

Disclosed is an auto injector and a method for administering a medicament. The auto injector comprising: a housing; a cartridge receiver; a drive module coupled to move a plunger rod configured to move a first stopper; a temperature sensor configured to provide a temperature signal indicative of the temperature of the medicament in the cartridge; a processing unit configured to: receive the temperature signal; control the drive module to move the plunger rod from a first plunger rod position to a mix plunger rod position wherein the movement from the first plunger rod position to the mix plunger rod position is based on the temperature signal; control the drive module to move the plunger rod from the mix plunger rod position to a second plunger rod position after a reconstitution time has elapsed since completion of movement of the plunger rod to the mix plunger rod position; wherein the first plunger rod position is a pre-mix plunger rod position, and the pre-mix plunger rod position is selected to position the first stopper in a position wherein fluid communication between the first cartridge subcompartment and the second cartridge subcompartment is not yet established, and wherein the second plunger rod position is a prime plunger rod position, and the prime plunger rod position is selected to position the first stopper in a position wherein air in the cartridge compartment is reduced to an amount appropriate for injection.