An aerosol generating apparatus includes a vial, a cap assembly and a receptacle. The vial stores liquid medicament and includes a puncturable seal held in position by a retaining ring. The cap assembly includes an actuator with an interior bore extending therethrough, a perforated membrane coupled to the actuator, a fastener and a first mating element. The fastener is adapted to detachably secure the cap assembly to the vial such that the perforated membrane aligns with the puncturable seal. The receptacle receives the cap assembly with the vial. The receptacle includes a driving element and a second mating element capable of mating with the first mating element. The driving element aligns and communicates with the perforated membrane when the receptacle engages the cap assembly. The actuator pierces the puncturable seal to displace the liquid medicament through the interior bore to the perforated membrane and the driving element to generate aerosol.