i've dabbled with benydryl too. nyquil too. i found that it made me very irritable during the day (especially the nyquil) so much so that i snapped at a customer and got "written up" at work......very uncool.
there are so many other ways to fight insomnia.........avoid caffeine, exercise, chamomile tea, peppermint tea, bedtime snack, warm milk (i can't sleep on an empty stomach). no one ever gets a really perfect night's sleep, not in "our" world.
but for those who have a true addiction to these OTCs and it is affecting your health as badly as vomiting blood, the best thing to do is see a doctor quickly.