Blue pills a doctor might provide (3)
I believe the answer is:
sad
'blue' is the definition.
(I know that blue can be written as sad)
'pills a doctor might provide' is the wordplay.
'provide' indicates the answer is hidden within the clue.
'SAD' can be found hidden inside 'pills a doctor might'.
(Other definitions for sad that I've seen before include "Melancholy, downhearted" , "Sorrowful, unhappy" , "Miserable" , "Disconsolate" , "Melancholy, triste" .)