Stung by scrap -- then dismissing hospital (6)
I believe the answer is:
bitten
'stung' is the definition.
('bitten' can be a synonym of 'stung')
'scrap then dismissing hospital' is the wordplay.
'scrap' becomes 'bit' ('bit' can be a synonym of 'scrap'**).
'dismissing' is a deletion indicator.
'hospital' becomes 'h'.
'then' with 'h' taken out is 'ten'.
'bit'+'ten'='BITTEN'
'by' acts as a link.
(Other definitions for bitten that I've seen before include "Attacked by, eg, an insect" , "Torn by teeth" , "Once ..., twice shy, it's said" , "Attacked with teeth" , "Once this, twice shy they say" .)