Can I use the word "perk" in my game?

I’m making a game where at the start the player have taken a potion which is still in the experimental stage, which is a part of the level up mechanic. When a player level up they can spend one point in the potion’s tree to unlock a side effect. I have been thinking of calling them perks, but the thing is not everything in that tree is good, so I’m not sure perk suits those negative effects.