Shouldn't be drunk, so ought to be dismissed from some thoughts (5)

I believe the answer is:

meths

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'shouldn't be drunk so ought to be dismissed from some thoughts' is the definition.
I can't tell whether this definition defines the answer.

'drunk so ought to be dismissed from some thoughts' is the wordplay.
'drunk so' becomes 'me' (I can't justify this - if you can you should believe this answer much more).
'to be dismissed from' is a deletion indicator.
'some thoughts' becomes 'thoughts'.
'thoughts' with 'ought' taken away is 'ths'.
'me'+'ths'='METHS'

Can you help me to learn more?

(Other definitions for meths that I've seen before include "unsuitable alcohol" , "Methylated spirits (colloq.)" , "Spirit" , "Fuel" , "Violet-coloured alcohol" .)

I've seen this clue in the Evening Standard.

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