My wife has always had a really weird condition. It's pretty harmless, but I thought I'd try to figure it out anyway.

If she drinks coffee with cream & sugar, and stirs it with a wooden coffee stirrer, like the ones you find in coffee houses, she gets a sore throat. Every time.

This never happens with just wood, like using a toothpick; only in conjuction with coffee. This also never happens if she uses something metal or plastic to stir the coffee. Just wood.

The only things I can come up with are:

  1. She has an allergy to the particular species of wood used only(?) in coffee stirrers, or
  2. Wood, when exposed to coffee (or sugar, or cream) produces a chemical to which she is sensitive.