Have had severe pain on descent for years, and kept losing the Earplanes plugs, draining the Fess saline spray, chewing the gum and still having problems.
Recently had the Avamys/Nasonex prescribed by the ENT surgeon, and now seem to get mild blockage only, and no more pain. Been spraying daily, but at least do not have to take the spray on board.
The effects seem to take a while, so he needs to start weeks before you fly.
And despite claims to the contrary, these sprays don't seem to cure snoring or hay fever.
Depends on the main symptoms of the hay fever and cause of the snoring, but many people get great hay fever results from them for this. Never thought about using them for snoring though.