I was prescribed vicodin (5/325) for back pain (take 2 as needed every 4 hours)... and I noticed when I take 2 my hearing becomes very sensitive. For example, if I am watching a movie in my room, the audio will sound "clouded" and cause a pressure-like discomfort. Its very hard to describe.

This also happens when I am in class (college) and professor speaks at like a expressive point (something they want you to remember). What I am hearing turns into this dull, pressurelike ache in my ear.

This also happened when given percocet after being in the hospital last year.

Anyone know what causes this?

Also, almost every other time I take the medication, I became easily irratated by others for no reason.

I am kinda looking for detailed answers on why vicodin causes this in my system (and others).

Please don't lecture me on the dangers of narcotics, all I seek is an answer.