Radical doctor having wine with bit of cocaine (7)

I believe the answer is:

drastic

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'radical' is the definition.
(drastic can mean radical or extreme)

'doctor having wine with bit of cocaine' is the wordplay.
'doctor' becomes 'dr' (abbreviation).
'having' says to put letters next to each other.
'wine with' becomes 'asti' (Italian wine. I am not sure about the 'with' bit.).
'bit of' indicates taking the first letters.
The initial letter of 'cocaine' is 'c'.
'dr'+'asti'+'c'='DRASTIC'

Can you help me to learn more?

(Other definitions for drastic that I've seen before include "Desperate" , "Radical, brutal" , "Severe - powerful" , "Uncompromising" , "Harsh, severe" .)

I've seen this clue in The Times.

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