Wearable automatic injection device for controlled administration of therapeutic agents

A method for administering a therapeutic agent to a patient, the method comprising:

• providing a wearable automatic injection device operable without electrical power, comprising:
• a housing comprising a patient contact portion for contacting the patient,
• an administration assembly moveably disposed in the housing holding an administration interface for administering the therapeutic agent to the patient, the administration assembly moveable between a retracted position in which the administration interface does not protrude outside the housing and an extended position in which the administration interface protrudes outside the housing,
• a vessel provided in the housing for holding the therapeutic agent,
• a plunger actuation mechanism moveably disposed in the vessel for ejecting the therapeutic agent from the vessel into the administration assembly, and
• a barrier mechanism moveably disposed over an administration interface aperture in the housing,
• securing the wearable automatic injection device to the body of the patient or an article of clothing on the patient using the patient contact portion of the housing;
• and
• administering a volume of the therapeutic agent to the body of the patient using the wearable automatic injection device.