Begin to take effect, as medicine (4,2)
I believe the answer is:
kick in
(Other definitions for kick in that I've seen before include "get going" , "work" , "Come into effect" , "Start to take effect" , "Start working" .)
I believe the answer is:
kick in
(Other definitions for kick in that I've seen before include "get going" , "work" , "Come into effect" , "Start to take effect" , "Start working" .)