Percocet used for pain relief is a narcotic medication and prescriptions can prevent people from getting high on Percocet without medical reason.In fact, the Percocet high feeling can get you into lots of problems.
I think the formula of the perfume itself decides how fast it will spoil. My perfumes from Britney Spears Curious and Salvatore Ferragamo went bad within a year and a half. The Britney Spears one developed some precipitation and started smelling like alcohol, while the Salvatore Ferragamo just smelled plain weird.
Why regular smells make some people sick. People who feel sick when they smell and overpowering perfume may not necessarily be allergic, but may have a condition that results in the inability to get used to smells. Usually your smell perceptions diminish rapidly, for example when you walk into someone else's house or get into a new car you notice a different smell immediately. After a while, most people stop noticing them. However, some people have a chemical intolerance which means that the smells continue to be present.