Having gone three matches unbeaten at the start of the Premier League season, Mick McCarthy's team have lost their last four consecutive matches.
The slump in form has dragged Wolves down to 14th position in the table and Johnson knows defeat in the Black Country derby is unthinkable.
"We don't want five losses on the bounce - we'll be in dire straits if we lose again," said the former Birmingham defender in the Express and Star.
"We're looking to stop the rot, and, even if we don't perform well, we must get something out of the game.
"We want to put this run of defeats to an end and it starts against them."
Johnson's Wolves colleague, Stephen Ward, is also aware of the magnitude of the match, but has urged his club to stay calm.
"It's a massive game for us to come back into and one I'm looking forward to," the Irish left-back said in the Birmingham Mail.
"They are always massive occasions and games you want to be involved in.
"Last year we were disappointed we didn't win at The Hawthorns but then back at Molineux we gave the fans a bit of a treat with how well we played.
"We know it's going to be a tough game and both teams are in a similar sort of position and will be keen on getting the points."
He added: "But the key is not to get too carried away with the occasion and who you are playing because despite knowing it's a derby and how important it is, there are still the same amount of points up for grabs."
Source: Team Talk
Source: Team Talk