Campo's second booking was for allegedly throwing the ball away at a free-kick during Boltons 2-1 defeat at Highbury.
A statement on the FA's website says: "We can confirm that following the sending off of Bolton's Ivan Campo for receiving two cautions in his side's Premier League visit to Highbury on Saturday, referee David Pugh has informed The Football Association that, having viewed a video of the incident, he now wishes to withdraw the second booking.
"Therefore, only the first caution for dissent will be recorded against the player and he will not be required to serve a suspension."