A friend halved his dose of ADs overnight on the advice of his GP. He has predictably spent most of the last 3 days in bed virtually unable to move.
Meanwhile, the son of someone else I know in the same area was taken off his ADs cold turkey by his GP from one day to the next. He had a complete mental breakdown within the fortnight and hasn't left his house for 6 weeks. He's an adult but a member of his family has to be with him at all times.
I'm no expert but it seems fairly predictable that withdrawing such a strong so quickly is going to lead to problems.