Edinson Cavani had not found the net for three weeks, but made up for lost time with this winning brace.
It has been a bad week for both sides. The Partenopei were leading at Anfield until the 70th minute, then crumbled to a Steven Gerrard hat-trick. The Ducali were propping up the table, had scored just once in their last five games and there were reports Coach Pasquale Marino was facing the axe.
Blerim Dzemaili was suspended with Alberto Paloschi, Daniele Galloppa and former Parma striker Cristiano Lucarelli injured. From their 15 Serie A and B meetings here, Napoli had won seven and lost two. The last time this fixture ended in a stalemate was 2-2 on December 23 2000.
Napoli took the lead with a classic counter-attack from Parma's own corner. Juan Zuniga broke away down the right and waited for the perfect moment, drawing the defence so he could roll across for the unmarked Edinson Cavani.
Morgan De Sanctis was a little wayward on a long ball, but was fortunate that the referee spotted a Sebastian Giovinco foul on him. Giovinco's season has been wracked with injuries and he limped off to make way for Hernan Crespo after just 25 minutes.
Straight after coming on, Crespo had Parma's best chance of the game so far. He got the tap-in to a low Antonelli cross, but Morgan De Sanctis managed to parry with his knee from point-blank range.
Alessandro Lucarelli needed a crucial tackle to stop Cavani running totally clear on goal just before half-time.
Napoli came out fighting after the restart and rained shots into the area, which Parma tried to charge down in numbers. Antonio Mirante blocked Cavani's angled drive, then a smart Marek Hamsik solo effort skimmed the woodwork.
Parma started to come out of their shells, though, as Hugo Campagnaro was finding it difficult to deal with wily old fox Crespo.
Mirante did well to stick out a foot to deny Cavani, while at the other end Lucarelli's header hit the side-netting at the back post from a dangerous Antonio Candreva cross that had cut out De Sanctis.
Napoli secured the points five minutes from time with an audacious finish from Cavani. He combined with Ezequiel Lavezzi, then turned his marker to somehow drill in between the goalkeeper and the near post from a seemingly impossible angle.