Complain about health group creating a drug production facility (4,5)

'a drug production facility' is the definition.
(facility for growing drugs)

'complain about health group' is the wordplay.
'complain' becomes 'grouse' (grousing is a kind of complaining).
'about' means one lot of letters goes inside another.
'health group' becomes 'who' (I can't explain this - if you can you should give a lot more credence to this answer).
'grouse' placed around 'who' is 'GROW HOUSE'.

'creating' acts as a link.

Can you help me to learn more?