What to do if i have really bad allergies and because of this i develop a dark line across my nose. have anyone else experience this?

Allergic crease: An allergic crease is a very common physical sign seen in people with nasal allergies and itching who perform an "allergic salute". This action crease the nose and after repetitive "saluting" causes a crease to form across the lower part of the nose because this area is soft and pliable. Similar to bending a playing card and causing a crease. There's no danger but cosmetically could be noticed