If you have a recurring dream of this nature, try to urge your dreaming self not to panic or run away but to face the spiders, ghosts, vampires or whatever fills you with dread.
You may find that this puts an end to the dream once and for all.
If the cause of your dread is not so clear cut—for example, you are talking with a friend and suddenly feel anxious in your dream—your dreaming mind may be telling you that there is something about this person you fear at an unconscious level in waking life. You may feel that your friend is undermining you all the time with silly jokes about your weight or appearance. If, on the other hand, a hideous monster is about to devour you in your dream, this is a clear symbol of something you fear; your dreaming mind is telling you that, unless you deal with your anger, jealously or guilt will consume you.