Different between atropine and hyoscyamine

There is not much difference between them. Atropine and Hysocyamine are isomers of each other. Atropine is (+/-) Hyoscyamine, the tropic acid ester of tropine. The naturally occurring alkaloid is (-) Hyocyamine. Thus it can be said that Hyoscyamine is a racemic form of Atropine.

In other Words, Atropine is a racemic variety of tropine tropate, hysocyamine being the levorotatory enantiomorph of tropine tropate.