Can I drywall over top of existing drywall?

It s commonly done on ceilings, just a thinner dry wall is all. So sure you can do it, just be aware of any windows or doors that may be on this wall since it ll screw you up on the trims and you ll have to deal w/ that. If no windows or doors , its a good fix like you suspect..1 suggestion though.. pre mark all stud location on the wall there now, it ll make your life easier when you put it up. And use longer screws to get to the studding GL