Atropine

Atropine is an alkaloid (naturally occurring amine produced by a plant) extracted from the deadly nightshade (Atropa belladonna) and other plants of the nightshade family (Figure 1). It can also be chemically synthesized by the reaction of tropine with tropic acid in the presence of hydrochloric acid.

Figure 1. Atropa belladona flowers (left) and berries (right).

Atropine is a muscarinic receptor blocker in the autonomic nervous system. This means that it prevents acetylcholine from binding to and activating the receptor and therefore it reduces the muscle contraction.