Emetic -- damn awful cure! (10)
I believe the answer is:
medicament
'cure' is the definition.
(thesaurus)
'emetic damn awful' is the wordplay.
'awful' is an anagram indicator.
'emetic'+'damn'='emeticdamn'
'emeticdamn' anagrammed gives 'MEDICAMENT'.
(Other definitions for medicament that I've seen before include "Healing substance" , "drug?" , "Curative substance" .)