'antidysenteric' originates from Greek elements: the prefix 'anti-' meaning 'against' and 'dysenteric' from Greek 'dysenteria' meaning 'diseased intestine' (literally 'bad intestine').

'dysentery' comes from Greek 'dysenteria' (dys- 'bad' + enteron 'intestine'), passed into Latin and Middle English as 'dysentery'; the adjective 'dysenteric' developed from that noun, and modern medical English formed 'antidysenteric' by adding the prefix 'anti-' to mean 'against dysentery'.

Initially, the components indicated 'against dysentery' and the combined word has retained that medical meaning of 'preventing or curing dysentery' (sometimes broadened to include related antidiarrheal action).