Medium could have therapy afterwards to treat disease (5)
I believe the answer is:
radio
'medium' is the definition.
(I know that radio is a type of broadcasting)
I don't understand the rest of the clue.
Can you help me to learn more?
(Other definitions for radio that I've seen before include "It used to be called the wireless" , "Receiving device" , "Electronic medium of communication" , "Transmit" , "send a message" .)