I guess two questions really. Is there a thread that has the events listed and what they mean?

one of my ladies drank a mysterious red liquid and I am wondering if all it was supposed to do is change her hair color, it's all I noticed after she said she didnt feel quite like herself.

when my villagers drak it all but one of my villagers where sick. (I wish all it was was just changing his hair colour )

What does the blue vial do?

Sometimes the red vial changes the look of the villager - you have to be quite observant to really notice (especially if you have a lot of villagers). Before you choose to drink it - remember what the villager looks like, then they change! I find this event very amusing!

Sometimes the vials add or remove skill when the villager "doesn't feel like themselves" -- so you have to know their skills to figure out something happened.

I've never seen them change appearance, so that's pretty cool (you can also change their appearance with the F6 key, I believe -- search the forums and you'll find some discussions about it).

I don't know if there's a relationship between the color of the liquid and the effect -- I didn't bother to keep track of what liquids my villagers were drinking .