Going off Adderall

Hello, all.  I am new to this forum and need some help or insight.  Until last month, my husband went to the same psych since he was 15 years old for his ADHD treatment.  He is now 43.  He is now at a new doctor after years of me suggesting he should switch.  The old doctor was giving off some strange signs and I didn't trust her.  The new doc was horrified to learn the daily Adderall dosage that my husband was prescribed.  My husband explained that the old doc used to switch his meds when one stopped working but that about 4 years ago, she stopped doing it even when he would request something else.  The new doctor suggested that for some reason, maybe her script privileges were revoked or under investigation and that she may only be allowed to write scripts for certain meds.  At this point, the extremely high dose of Adderall is not effective and the risk to his heart health are high.  The new doc suggested going off the Adderall and trying Nuvigil to at least help with the extreme fatigue that he would most likely experience due to stopping the Adderall.  The doctor gave him the option of going cold turkey or weaning off.  This past Saturday he went off cold turkey.  He was excited to see if perhaps he no longer needed the Adderall or at least if he took a holiday from it, maybe he could start back on a very low dose.  Well, here we are 3 days later and he has crashed.  He couldn't go to work today and I am worried.  I wonder how long this crash might last.  I may be over-reacting but what if he never comes back up again?  The nuvigil at 150 mg seems to do nothing which doesn't surprise me considering how high his Adderall dosage was.  And, I am steaming mad at the previous doctor for putting my husband in this situation.  She should have her license revoked.  The scariest part is that she is a child psych.  What if she does this same thing to children?  Has anyone else encountered this type of situation?  Do you have any idea how difficult this might be and how long it might take for the crash to subside?