Indeed, but a "Cure for a hangover" is the name for more booze, same thing really. I've forgotten the Lunfardo word for hangover, but that'd only be useful if you're inviting any Porteños.
Cheating and looking at the
Wikipedia page, it gives "pelos de la misma chancha" as being used in Costa Rica, but there's no guarantee that "hair of the pig" would be meaningful to a Spaniard (or anyone outside Costa Rica for that matter) given the subtle differences between the language in each country (I carefully avoided asking to fuck the bus in South America).