A.L.
I feel for you! My 5 year old daughter has them about 3 times a week. I feel like a horrible mom when i can not calm her down. She just screams and doesn't stop for about 4 min. We have recently gotten a sound machine that has a waterfall noise and we spray "monster spray" really just water every night to keep the monsters away and the good dreams close. Also I have found that a early bedtime before she is to sleepy (around 8 or 8:30 for us) and no sweets after 6. Seem to help also we have cut out Spongebob, Jimmy Newtron, and Fairly Oddparents. We found that these cartoons were actually kinda scary if you would dream about them. Now she watches more child friendly cartoons, I hope this helps, I really do. I know how hard this is to deal with.
A.