Camera FX to fade out back to normal

Hello, I've searched Google for awhile and can't seem to find what I'm looking for.

I have a camera effect that simulates "tripping" or being "high". When my character eats a certain amount of mushrooms the camera effect is called and the screen becomes blurry with various colors. However, after awhile I would like those effects to fade off back to a normal screen.

Any suggestions?