One new pal is patient (6)
I believe the answer is:
inmate
'patient' is the definition.
(inmate is a kind of patient)
'one new pal' is the wordplay.
'one new' becomes 'in' (I've seen this in other clues).
'pal' becomes 'mate' (I've seen this before).
'in'+'mate'='INMATE'
'is' acts as a link.
(Other definitions for inmate that I've seen before include "Person confined to institution" , "One is confined to an institution" , "eg Prisoner" , "Convict" , "One held in prison" .)