Medical ethics?

I've got a m8 who's working in a lab and he was reading some h&s stuff last night. Apparently if you ingest ethyl glycol the treatment is immediate administering of alcohol. The reason they keep a bottle of Vodka in the fridge no doubt. Anyway I said what if the patient is a recovering alcoholic? You know you'll save his life but will it be worth saving once you've pushed him off the waggon?

I mean you wouldn't give a JW a blood transfusion or a vegan a pigs heart would you?

I'm not making light of the subject and he tells me hundreds of children and pets are killed or left with serious side effects after drinking anti freeze every year so if you've been affected I don't mean to offend.
What would you do faced with this situation? Sorry I missed the question bit out lol