Dilaudid has less of an effect on the bowels than other opiates in the same potency class. My guess is that it's an alternative for people who are overly sensitive to the constipation.

Morphine's (ala MSContin) not very active orally, either. I think it's just another marketing strategy. Maybe OxyContin's black box warning boosted sales of MSContin, so they see a new opportunity? I'm certain it will be a big hit with drug addicts, though...

-yawkaw