In (Canadian?) French, we have an expression, "j'ai envie" (litteraly: I want), which, when used without any subject, means that the speaker needs to use a toilet, either to urinate or defecate. It is somewhat informal; you would prefer saying "I need to use the washrooms" rather than that in a very formal context, but it would still be accepted. Is there any such expression in English? What is the most popular way to express one's need to use a toilet?
I am specifically looking to translate the following:
Quand je mange des produits laitiers, ça me donne envie
(When I eat dairy products, [I need to use the washroom])