Portable injection appliance

A portable appliance for subcutaneous or intradermal injection of a liquid formulation of an active principle into a patient comprising:

• a housing having a patient engaging surface to contact a patient's skin;
• a supply vessel positioned within said housing for storing the liquid formulation;
• infusion needle means having an infusion needle and positioned in said housing, said means used for establishing communication between said supply vessel and said infusion needle when said infusion needle is activated to advance into the patient's skin a preselected distance;
• pump means for emptying the liquid formulation from said supply vessel through said infusion needle means;
• needle driving means for subcutaneous or intradermal injection of the infusion needle through the patient engaging surface and into the patient's skin through an injection site the preselected distance;
• and
• securing means for securing the patient engaging surface of the appliance to a portion of the patient's skin substantially surrounding the injection site through which the infusion needle enters the patient's skin thereby providing a tight adherence of the patient engaging surface to the patient's skin.