This phrase is never meant to be taken literally. No-one really injects
coffee directly into their blood stream. Caffeine is the main ingredient of
coffee, and gives us a feeling of satisfaction. It is simply a joking expression which refers to an intense
love, or even addiction, to coffee.
I'm going
nuts - If I don't shoot caffeine intravenously soon I'm going to fall out of my tree!
When I was
13 I had my first
coffee, and I've been practically shooting caffeine intravenously ever since!