Mitigates some disease symptoms (5)
I believe the answer is:
eases
'mitigates' is the definition.
(I've seen this in another clue)
'some disease symptoms' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'EASES' is hidden within 'disease symptoms'.
(Other definitions for eases that I've seen before include "Makes more comfortable" , "Makes less severe" , "Calms" , "Lessens tensions" , "Borders, margins" .)