A medicament respiratory delivery device including a housing formed of opposed thermoformed polymeric sheets bonded together having formed therebetween a chamber having a medicament cartridge encapsulated between the sheets, an inlet aligned with a passage through the cartridge having a pierceable closure and an outlet aligned with the passage outlet having a burstable membrane. The device includes a pressure actuator formed as a blister between the sheets and a piercing element having a bow-shaped actuator portion and a shaft which pierces the pierceable closure upon actuation of the pressure actuator, delivering fluid under pressure to the cartridge passage, rupturing the membrane and expressing the medicament.