Someone has this syndrome when normally they are cool and alright to be around. Sometimes, though, instead of being forgetful or mixing up numbers like a dyslexic they act like a douche, usually without warning and in public.
Me: Why is Eddie ready to fight that guy who bumped into him? Eddie's usually calm and the guy apologized too.
You: He's douchlexic. Occasionally he acts like a Douche and everyone knows he's wrong.