Tobacco or Scopolamine are high on the list.

One may be prescribed Scopolamine as an option to treat depression. It is a drug that is found in some depression medications, and is prescribed in very small doses because it is very dangerous to take too much.

an adhesive medication patch that is applied to the skin behind the ear.

I bought it OTC at Shopper's Drug Mart (Canadian pharmacy).

From my understanding there is not much of a difference. Atropine and hyoscyamine are isomers of each other but other than their shape position, they are the same. Scopolamine has a chemical structure that is very similar but a little bit different, thus it is mostly recognized in the body as the same chemical as the former two.