No, I'm afraid no movie will show anyone being administered an enema... unless someone has another record ?
But there are movies showing enema equipment, as part of the background or sometimes the foreground; no special enema interest but...
Watch the mid 70's disco musical "Car Wash" : apart from a good sound and a very good chart position at that time, you will see a young lady entering toilets and get her equipment out of her hand bag, hanging it, and you have to guess what she does next, until you see her again "after", with the empty bag, tube and tip hanging over the toilet. No enema action but it was a surprise to discover these images in an "all audiences" movie; was it as common as this in the mid 70's ? Just can't remember;
As anyone seen something like this in other movies ?