A telescoping portable drug mixing and delivery device configured to store a dry medication separately from a liquid component, wherein a tensile force applied between the housing and a cap opens a valve and causes displacement of a fluid from a first chamber to a second chamber while simultaneously mixing the fluid with a dry medicament prior to injection. An extendable needle guard is provided over the delivery assembly which prevents premature injection as well as inadvertent sticks or other cross contamination of a needle. The needle guard can also form part of a secondary trigger mechanism which injects the reconstituted drug after the mixing stage is complete.