Carebear, hope you find some things that help you; hope you will post what has been effective.

I agree with the other posters: talking with someone, writing down these dreams, looking for a common theme may be helpful. Sometimes I can figure out, days later, what the scary symbolism stands for in my life: challenges, things that need to change, fears, etc.

I've used some of what Omegalamed suggested: turn on a light, remind myself it's just a dream, have something soothing to drink.

I keep a few non-stimulating books and articles on my phone that can help soothe me. (by non-stimulating, I mean I need writing that is not suspenseful, dark, violent - textbooks are great for this!). Even something that can make me laugh - as in DBT, using the "other emotion" skill, where you deliberately try to trigger an opposite emotion (so, something silly that makes me laugh, brings me out of my fears).

Maybe even posting here, or speaking with an understanding friend, who will just speak about neutral/pleasant things to help bring you out of it? I have a friend who I can text if I'm scared. She may not always be up to respond, but I feel better just sending something out to someone who cares.

Take care!