Long term use of Nasal spray and it's effects.?

Ill be honest I didn't read your entire posting but my dad is 73 years old and he's been using nasal spray like ALL of his life. He literally sleeps with it under his pillow haha. But he's never had any side effects and if anyone would get them it would be him. He uses vicks its like a white bottle with a blue cap idk if there are differences in the different brands.