Such sickness and suffering orig­inate with medic, ultimately (10)

'such sickness' is the definition.
(as in iatrogenic illness)

'suffering originate with medic ultimately' is the wordplay.
'suffering' indicates anagramming the letters.
'with' says to put letters next to each other.
'ultimately' suggests the final letters.
The last letter of 'medic' is 'c'.
'originate' anagrammed gives 'iatrogeni'.
'iatrogeni'+'c'='IATROGENIC'

'and' acts as a link.