What's The Difference Among The Following Expressions???
To Keep Your Wits About You:to be alert and resourceful
e.g:if he hadn't had his wits about him,he might have been drowned
At My Wits' End:in despair of finding a solution to one's problems.
Scared Out Of My Wits:(I found this idiom: to frighten sb out of his/her wits). I think it is what you mean
meaning:to terrify sb so much that she or he is unable to think properly .e.g: That Alsatian of the Masons frightens me out of my wits whenever I pass their house;they should keep it chained up.