What dulls headache that is new for boozer turning in? (9)

I believe the answer is:

ibuprofen

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'what dulls' is the definition.
I can't tell whether this defines the answer.

'headache that is new for boozer turning in?' is the wordplay.
'headache' becomes 'ie' (I can't justify this - if you can you should give a lot more credence to this answer).
'that is new' becomes 'n' (common abbreviation eg NT for New Testament).
'boozer' becomes 'pub' (UK slang).
'turning' says the letters should be written in reverse.
'in?' is an insertion indicator.
'for'+'pub'='forpub'
'forpub' written backwards gives 'buprof'.
'ie'+'n'='ien'
'ien' going around 'buprof' is 'IBUPROFEN'.

Can you help me to learn more?

(Other definitions for ibuprofen that I've seen before include "Drug" , "anaesthetic" , "Anti-inflammatory medicine" , "Painkiller" .)

I've seen this clue in The Independent.

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