Railing against yellowish-white lotion? (7,5)
I believe the answer is:
barrier cream
'lotion?' is the definition.
(barrier cream is a type of lotion)
'railing against yellowish-white' is the wordplay.
'railing' becomes 'barrier' (railing can mean a bar or barrier).
'against' is a charade indicator (letters next to each other).
'yellowish-white' becomes 'cream' (yellowish-white colour).
'barrier'+'cream'='BARRIER CREAM'
(Other definitions for barrier cream that I've seen before include "Dressing used to protect the skin" , "It protects hands from dirt etc" , "that'll save his skin" .)