Rouse is fairly uncommon in spoken English in the US. It sounds old fashioned, like something an author from 100 years ago would use. Arouse is more common and it is more commonly used in the adjective "aroused" or the noun "arousal" meaning attraction to someone. Aroused is also used in the medical sense of being awake and alert, but usually only by medical professionals.
What context do you want to use it in?