Here's the problem. It isn't always easy to spot an addict. As Seth Mnookin (perhaps the best writer out there when it comes to issues of addiction) points out in an excellent critique of A Million Little Pieces, there are plenty of functioning addicts in the world. House need not be shown as a homeless junkie to represent the reality of addiction. But just because House falls into the functioning category rather than the stereotypical junkie category doesn't mean that his disease is somehow non-debilitating.
It's obviously not the job of the House writers to prove to the world that Addiction Is Undesirable -- we are, after all, talking about a drama, not a documentary. But it irks me nonetheless that the only episode in which we've seen the negative effects of House's addiction (at least, the only episode I'm aware of, although I haven't yet seen them all) was the one in which Cuddy made House stop taking his pills. Look, Ma, his withdrawal symptoms were worse than the addiction itself! Hey, he's an addict, but it doesn't get in the way of his ability to make the brilliant diagnosis week after week after week! And yes, he's a crotchety son-of-a-bitch, but that's just part of his prickly genius! And isn't it really kind of lovable, after a fashion?
I don't think I'm going out on a major limb when I say that generally speaking, drug addiction sucks. If you haven't personally witnessed the degree of suckiness, consider yourself fortunate. In my experience, for every functioning addict in the world, there's another shoe out there waiting to drop. Maybe we'll see the one earmarked for Gregory House, M.D., and maybe we won't. But make no mistake about it: the shoe is out there, no matter how brilliantly House functions while we wait to hear it fall to the ground.