Drink starts to take effect afterwards (3)
I believe the answer is:
tea
'drink' is the definition.
(tea is a kind of drink)
'starts to take effect afterwards' is the wordplay.
'starts to' suggests taking the first letters.
The initial letters of 'take effect afterwards' is 'TEA'.
(Other definitions for tea that I've seen before include "Assam, e.g." , "Char" , "Beverage; meal" , "Infused leaves" , "Dried leaf infusion" .)