What follows this pill potentially is safer to swallow? (5,4)

I believe the answer is:

truth drug

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'what follows this pill potentially is safer to swallow?' is the definition.
The definition suggests a singular noun which matches the answer.

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(Other definitions for truth drug that I've seen before include "that may provide required information" , "Supposed means of preventing lying" .)

I've seen this clue in The Times.

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