Iodine found in Cream Crackers - get first aid for us! (7)
I believe the answer is:
america
'us' is the definition.
(I have seen 'The US' mean 'america' so perhaps 'us' could also mean 'america')
'iodine found in cream crackers get first aid' is the wordplay.
'iodine' becomes 'i' (I is the chemical symbol for iodine).
'found in' means one lot of letters goes inside another.
'crackers' indicates an anagram (informal term for mad).
'get' means one lot of letters go next to another.
'first' suggests taking the first letters.
The first letter of 'aid' is 'a'.
'cream' is an anagram of 'amerc'.
'i' put into 'amerc' is 'americ'.
'americ'+'a'='AMERICA'
'for' is the link.
(Other definitions for america that I've seen before include "Continent named after Vespucci" , "Land of the free and home of the brave?" , "Take care and aim for the continent" , "Camera I used in New World" , "Continent of the Western Hemisphere" .)