Having come to the decision to go through with the test, I can understand your frustration after taking your son off the medication,  when they failed to get blood!  My son was actually admitted to hospital for this test (so they could monitor him whilst off the medication). A canula was put in his arm on admittance,  in order to take the blood the following morning and also so the ACTH could be adminstered IV.  Like your son, he didn’t seem to suffer any ill effects from the lack of medication .  I am sorry to hear the staff were so unhelpful and unsympathetic - that is appalling.  I hope there isn’t so much trouble next week getting the blood for the DNA test.  Once again - good luck with this!