Male cutting chest is upset -- they'll provide medicine (8)
I believe the answer is:
chemists
'they'll provide medicine' is the definition.
'male cutting chest is upset' is the wordplay.
'male' becomes 'm' (common abbreviation).
'cutting' indicates putting letters inside (some letters cut their way into a word).
'upset' indicates an anagram.
'chest'+'is'='chestis'
'chestis' anagrammed gives 'cheists'.
'm' put inside 'cheists' is 'CHEMISTS'.
(Other definitions for chemists that I've seen before include "Apothecaries" , "They dispense prescriptions" , "They're trained in the natural sciences" , "Drug dealers" , "Scientists" .)