Doctor sent robust medicines to block passages (10)

I believe the answer is:

obstruents

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'medicines to block passages' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.

'doctor sent robust' is the wordplay.
'doctor' indicates an anagram.
'sent'+'robust'='sentrobust'
'sentrobust' with letters rearranged gives 'OBSTRUENTS'.

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I've seen this clue in The Hindu.

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