A fork of Rural Dictionary
When the area around your penis begings to itch.
"Gawd, I have an itchy penis!"
Itchy penis disease is a severe thing that happens whenever you dip your ding a ling in melted chocolate and then put it in a Bootyhole that has been coated extra thick with peanutbutter. Then the girl eats the peanutbutter and chocolate off of you.
I totally got itchy penis disease last night.