Abstract: The present invention relates to a dial-down mechanism for an injection device comprising a torsion spring for assisting injection of a dose of medicament from the injection device, the dial-down mechanism comprising dial-up cam arranged to receive and engage with a dial-up key, wherein the dial-up cam and the dial-up key are adapted to, upon rotation of a dose setting member in a first direction, cooperate to strain the torsion spring of the injection device, and a dial-down cam arranged to receive and engage with a dial-down key, wherein the dial-down cam and the dial-down key are adapted to, upon rotation of the dose setting member in a second direction, cooperate to release the torsion spring of the injection device, the second rotation direction being opposite to the first rotation direction.