We should not forget old wisdom, or folk medicine.
Yugort is good for diarrhea, so is heavy tea without sugar

In grid-down, or general hard times, or any kind of unforseen stuff, local or old medicine always saves the day. I remember two years ago, I was at my brother's house in another town. I got a bad toothache out of no-where. I was far from my well-stocked pantry and medicine cabinet. He brought me a small piece of mihr (?sp?). I just put it on my tooth for half an hour and I was OK. Since then. mihr(?sp) is always present in my portable pharmacy. It works as local pain killer , and antibiotic.

So, same goes for herbal teas, like mint, hibiscus, thyme , anise, and others.