I tried this one, actually. Well, my reason for admission wasn't a failed attempt, but I was involuntarily admitted nonetheless. Thank god I did not get forcefed but on day 3 or so, I was (involuntarily) transferred to a medical hospital and (involuntarily) given iv fluids. Shortly thereafter I gave up and started eating again. Not much use in refusing food while being forcibly rehydrated.
So sadly, it's probably not the best strategy. You'd be better off playing nice in the psych ward and pretending to care about recovery so you can get your ass back home and attempt again (if you so choose) in safety.