@forteller looks good to me (Northern California, USA)
That depends on the idea you are expressing, and how you wish to express it.
The word "refrain" could speak to the overwhelming desire to howl, to chase, and to rip sweet flesh with sharp teeth. If the professor still feels a longing to do so when bathed in moonlight, even after drinking the potion, then "refrain from" or "resist" might do.
"Prevent" or "avoid" suggests an action done to avert an unwanted outcome, like eating one's tasty friends.
@jannamark @seanl Good point! :D Thanks!
@jannamark Thanks! You don't agree with @seanl here? https://social.literati.org/@seanl/99694713097150157