I can not leave the lips for more than a week and if i do, they detach by themselves after a week, actually, i always try to leave them longer than a week, but they start to be like a corn flakes, specially the bottom lip and in my case it started as a white dead skin cells (when getting up in the morning)and not as a wound, so, i dont think that leaving them alone helps, i stongly believe that it is internal chemical imbalance due to stress and other problems but the medical Science is not paying attention about this problem.