DANIEL WAGNER, MD: An acute insomnia is one that lasts less than two weeks. And in most cases, has an identifiable precipitant. Something happens or you have some big test coming up or a big presentation or something and you have trouble sleeping on account of that. And then once that situation passes, the insomnia goes away. That's usually trouble getting to sleep, but it may be trouble maintaining sleep as well.
DAVID FOLK THOMAS: And, Dr. Zak, what about the chronic form of insomnia, what is that?
SHELLEY ZAK, MD: This is the most difficult and this is the one that ends up lasting beyond a month. Multiple times during the week, you're waking or not being able to maintain sleep. And this is what we see most commonly. I think people with something that's acute, either it just passes or they go to their primary-care physician.
And chronic insomnia's often start from acute insomnias. We like to talk about perpetuating factors. In fact the irony is that some of the things people do to compensate for their short-term insomnia can promote insomnia and have it continue. So, for example, you don't get enough sleep. Well, the next night, you might try to go to bed much earlier than you should and spend too much time in bed. This doesn't get you any more sleep, it just fragments it and it has it become more unrefreshing.
Another thing people do, "Ah, I didn't get enough sleep, drink a lot of coffee." Well, that's fine, to some degree, because it can promote wakefulness at some level, but if you drink too much it will give you difficulty falling asleep the next night and then, again, you perpetuate it.