The Shulchan Aruch mentions in a few places that if wine is not available then one may
use chamar m'dina (a national drink), for bentching, kiddush, and havdala. chamar m'dina is also permitted if one cannot tolerate wine.
Question: What are the qualifications for chamar m'dina ? Can any drink be used ? Must it be a popular drink in the place where the person wants to use it ? What about bottled water ? In short what are the guidelines for choosing which drink to use for chamar m'dina ?
It basically means a drink which is popular in the area in which you are (Pesachim 107a). The Shulchan Aruch says it's anything except water. Rav Moshe Feinstein says that it's any drink which you would drink when you weren't thirsty. In other words, things you drink socially like beer, whiskey, and tea. (Iggrot Moshe, Orach Chaim 2:75).