That's an interesting question because I have never been able to take just one after a "slip." Be interesting to hear an answer to that one.
One time I relapsed for 2 weeks or so - had w/d's. Not as bad but still had them. Just depends on what you take. It is almost impossible to take just one for me.
With my pain management meds, a slip involves 150 10/325 Norco's and I have not ever been able to "Take as needed" or follow dosage instructions. (I burned through them in 8 days last time and then burned through 120 7.5 Lortabs the next 10 days.)
My PCP Doc. says 2 weeks is the maximum anyone should be on pain meds and he feels that physical WD symtoms will occur after that (I presume based on his experience with patients).
Just my $0.02, YMMV
That is a very interesting question, and I have no idea of the answer, but I too would be very interested to know. Not that I am planning to slip or anything.