I think to make any headway at all with that condition you have to make sure the CS comes in contact with all of the infection, oral use won't do enough, though it would be good to do that in addition to spraying the sinuses. I would spray the sinuses once every waking hour until I got some relief. The DMSO is highly recommended to help the CS penetrate though, so if the CS alone doesn't get it you know what is needed. Try the CS alone first and see if you can make some progress.