Patent ID: 8753310

Claim:
A method for preparing a medicament prior to delivery into the body of a patient by injection into or through the skin of a patient, comprising: providing a first reservoir having a flexible, non-distensible membrane, the first reservoir containing a substance at a predetermined pressure; providing a needle in selective communication to said first reservoir; providing a second reservoir having a chamber with at least one movable wall, said chamber containing a fluid, said chamber having a pressure greater than said predetermined pressure; causing fluid communication to occur between said chamber and said first reservoir whereby said fluid communication allows said fluid to flow between said first reservoir and said chamber and co-mingling of said fluid and said substance to form said medicament; moving said at least one movable wall of said chamber whereby said moving forces said medicament to flow from said chamber into said first reservoir, whereby said medicament is prepared for injection; delaying pressurization of said first reservoir until substantially all of said medicament has been forced into said first reservoir; and pressurizing said first reservoir and infusing the medicament into the body of the patient through the needle from said first reservoir.