Just out of interest, which part of your anatomy is in plaster?
Damn plasterers have plastered all my tools, dirty sods, does that count?
Know just how you feel, I was in plaster for 6 weeks in October when I broke my foot - not a happy bunny!
Worst part was being in plaster trying to get round on my birthday, definitely put a dampener on things!
Amazing too how much you take for granted, even having a bath and being able to relax!!!
As for tips to deal with the itching n stuff (and yes, it will itch!), wherever your plaster is, get your hairdryer and blow cool air down it, it helps to stop the itching.
You have my sincerest sympathies........