She is taken off coaches' stimulant (4)

I believe the answer is:

coca

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'stimulant' is the definition.
(I've seen this before)

I don't understand the remainder of the clue.

(Other definitions for coca that I've seen before include "Drug-producing plant" , "Shrub yielding drug" , "Leaves for snow" , "Source of drug" , "Drug-yielding shrub" .)

I've seen this clue in the Irish Times (Crosaire) and the Irish Times.

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