Wait wait wait if your a mha weeb read this OK ,
so bakugou has nitrogliserin sweat right so he can make explosions soo he needs to get hot really easily right so he can overheat easily, so he takes pills so he doesn't overheat and the pills change his personality ((that's why he is always angry)) and he became mean to izuku (deku) when he got his quirk (when he started to overheat)

I think i found some thing out XD