Antibiotics is a really good one, I once got warned by my doc that this specific brand (bit stronger than most) would make me break out in a full body rash if I combined it with alcohol. That was for a mouth ulcer (my wisdom tooth was rubbing on my cheek and breaking the skin) and the germs from all that have me tonsillitis too.
My favourite though is just to keep it simple, say you're not having a really big one, and make sure you, DP or your mother (or anyone who knows if anyone) are the only ones who mix ur drink. Depending on what u normally have, just drink the non alcoholic version. Run and come fan? Just drink coke and ice. Wine? Get a bottle of sparkling grape juice from your supermarket. It's in the aisle where the beer brewing stuff is. No one will even notice the difference.