Holiday abroad perhaps is cure when restless (6)
I believe the answer is:
cruise
'holiday abroad' is the definition.
(holiday around different countries)
'is cure when restless' is the wordplay.
'when restless' indicates an anagram.
'is'+'cure'='iscure'
'iscure' is an anagram of 'CRUISE'.
'perhaps' is the link.
(Other definitions for cruise that I've seen before include "Voyage for holiday makers" , "Sail on a ship" , "Pleasure trip; type of missile" , "Sail to and fro" , "journey" .)