Guess cupboards hold two types of blood medication (4-8)

I believe the answer is:

beta-blockers

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'two types of blood medication' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.

'guess cupboards hold' is the wordplay.
I cannot quite see how this works, but
'hold' could be 'lock' (lock is a kind of hold) and 'lock' is located in the answer.
This explanation may well be incorrect...

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I've seen this clue in The Times.

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