Can I apply biluma cream on my knuckles and darken area and how long much can I use biluma cream im under 19 but knuckles arr much darker looks very bad I am not able to consult with Dr. So im asking here plzz ansr me I buyed biluma cream I wanna experience it cause I heard so much about this cream so I wanna use does it safe how long I use? And when stop then what to allow for permanent result.