Fix wise man’s prescribed amount of medication (6)
I believe the answer is:
dosage
'man's prescribed amount of medication' is the definition.
I can't judge whether this defines the answer.
'fix wise' is the wordplay.
'fix' becomes 'do' (I've seen this in other clues).
'wise' becomes 'sage' (similar in meaning).
'do'+'sage'='DOSAGE'
Can you help me to learn more?
(Other definitions for dosage that I've seen before include "Administered amount of drug" , "The giving of medication in prescribed amount" , "Medicine administered" , "Giving of medicine in prescribed amount" , "Sea dog (anag)" .)