If you're referring to the secondary applications linked to PharmCAS to each specific school, then they're not going to know if you copy and pasted your response from one school to the next. I wouldn't make it a habit of plagiarizing your own work but no one is going to know.
That said, don't copy and paste your answers that are directly linked to PharmCAS for universal submission since some schools will receive your primary (PharmCAS) coupled with their own secondary application(s).