Reduce tingle, working around hospital (7)
I believe the answer is:
lighten
'reduce' is the definition.
(thesaurus)
'tingle working around hospital' is the wordplay.
'working' indicates anagramming the letters.
'around' indicates putting letters inside.
'hospital' becomes 'h' (abbreviation for hospital on maps).
'tingle' with letters rearranged gives 'ligten'.
'ligten' placed around 'h' is 'LIGHTEN'.
(Other definitions for lighten that I've seen before include "Ease burden or reduce weight" , "lift" , "cheer" , "Make less serious" , "Make less burdensome" .)