It depends on what are you pressurized of.
If you sttudy hard under peer pressure to get good grades, then its good.
But, sometimes when you copy your peers just to look cool, then might bring negative consequesnces. for example, some people would wear funky clothes even if they don't suit on them, would smoke or drink alcohol under peer pressure.
Peer pressure sometimes make you kind of menatlly paralized. you can't think anything by yourself. You lose your indivisuality.