Hammilton,
Welcome to the forum.
I guess you've already come across this paper:
"Medication Tolerance and Augmentation in Restless Legs Syndrome: The Need for Drug Class Rotation"
Roger Kurlan, MD,1 Irene Hegeman Richard, MD,1 and Cheryl Deeley, RNP1
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1924754/
John