Rough patch? (4)
I believe the answer is:
acne
'rough patch?' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for acne that I've seen before include "Youthful problem" , "Skin condition prevalent among teenagers" , "Cane for the teenager?" , "Spotty coverage" , "Inflammation of glands in skin" .)