Hi GC, 6 years ago I did not produce sufficient stem cells after 3/4 days using granulocyte colony-stimulating factor, or GCSF self administered injections. At the end of the session I was then given a drug called plerixafor which they told me would take 12 hours to work (which it did almost to the minute, 3 separate flushes through my body as it seemed to release the stem cells) and I produced ample stem cells for 2 x STC’s the following day.