A medical injector is provided herein having a body a reservoir containing first and second mixable component a stopper a plunger a spring disposed to advance the plunger a first releasable retainer for releasably retaining the plunger in a first state against force of the spring a first trigger for causing the first releasable retainer to release the plunger a second releasable retainer for releasably retaining the plunger in a second state against force of the spring and, a second trigger for causing the second releasable retainer to release the plunger. The spring causes the plunger to advance so that the stopper traverses at least a predetermined extent of advancement thereby causing mixing of the first and second mixable components. Advantageously, with the subject invention, a medical injector is provided which allows for autoreconstitution with subsequent dose setting and autoplunger activation being activated by separate triggers.