As I had just bought rum aroma for some recipe, I had a quick look at the ingredients. It contains, according to the package (wait for it!):

• water
• aroma

Not very helpful. I suppose it's some kind of secret.

Anyway, I doubt it's alcohol related. It may be that we tend to eat a lot, and a lot of sugar these days. Not saying that explains all, but I know that for many people there is a relation between pain and large (larger than normal?) amounts of sugar (and flour).

Edit: some digging showed that it contains beeswax, shellac, carmine, yeast, beef gelatine, and "a lot of other components". They do claim it's approved for ovo-lacto-vegetarians though.

In short: who knows what's in it...