All of the previously referenced cases of DPD deficiency appear to have considerably less time to toxicity compared to thosewithout a DPD mutation according to the capecitabine package insert, which reports that the median time to first occurrence ofgrade 2–4 diarrhea is 34 days, and the median time to onset of hand-foot syndrome is 79 days (Pfizer, 2012). Here, DPYD is linked to hyperinsulinemic hypoglycemia, familial, 4.