Gallagher had been out for several weeks returning to the bench at Hillsborough before starting on Saturday against Cardiff. Preston's forward play has been lacking in the opening part of the season mainly through the fact that limited chances were being created.
Preston went to Charlton last night with an ambition to come away from the game with something as the South London side were in a similar position in the table.
Charlton were knocked flat when Gallagher scored from a free kick early in the game before he doubled the lead in the fist half. Daniel Johnson added a third in the second half to give Preston all thre points.
North End climb out of the relegation zone but it is very tight from bottom club Bolton all the way up to the middle of the table. Preston stay down south and will play Brighton who top the table on Saturday.