Behold, transformed into medication (6)
I believe the answer is:
lotion
'medication' is the definition.
(lotion is a kind of medication)
'behold transformed into' is the wordplay.
'behold' becomes 'lo' ('lo' is an archaic exclamation meaning 'look!').
'transformed' is an anagram indicator.
'into' with letters rearranged gives 'tion'.
'lo'+'tion'='LOTION'
(Other definitions for lotion that I've seen before include "Liquid for washing the skin" , "Salve" , "Medicinal or cosmetic liquid preparation" , "Liquid preparation applied to the skin" , "Embrocation" .)