The antidote to atropine is physostigmine or pilocarpine.A common mnemonic used to describe the physiologic manifestations of atropine overdose is: "hot as a hare, blind as a bat, dry as a bone, red as a beet, and mad as a hatter". These associations reflect the specific changes of warm, dry skin from decreased sweating, blurry vision, decreased lacrimation, vasodilation, and central nervous system effects on muscarinic receptors, type 4 and 5. This set of symptoms is known as anticholinergic toxidrome, and may also be caused by other drugs with anticholinergic effects, such as hyoscine hydrobromide (scopolamine), diphenhydramine, phenothiazine antipsychotics and benztropine. Contraindications
It is generally contraindicated in people with glaucoma, pyloric stenosis, or prostatic hypertrophy, except in doses ordinarily used for preanesthesia. Chemistry
Atropine, a tropane alkaloid, is an enantiomeric mixture of d-hyoscyamine and l-hyoscyamine, with most of its physiological effects due to l-hyoscyamine. Its pharmacological effects are due to binding to muscarinic acetylcholine receptors. It is an antimuscarinic agent. Significant levels are achieved in the CNS within 30 minutes to 1 hour and disappears rapidly from the blood with a half-life of 2 hours. About 60% is excreted unchanged in the urine, most of the rest appears in urine as hydrolysis and conjugation products. Noratropine (24%), atropine-N-oxide (15%), tropine (2%) and tropic acid (3%) appear to be the major metabolites, while 50% of the administered dose is excreted as apparently unchanged atropine. No conjugates were detectable. Evidence that atropine is present as (+)-hyoscyamine was found, suggesting that stereoselective metabolism of atropine probably occurs.
Natural sources
Atropine is found in many members of the family Solanaceae. The most commonly found sources are Atropa belladonna (the deadly nightshade), Datura innoxia, D. wrightii,  D. metel, and D. stramonium. Other sources include members of the genera Brugmansia (angels trumpets) and Hyoscyamus. Synthesis
Atropine can be synthesized by the reaction of tropine with tropic acid in the presence of hydrochloric acid. Biosynthesis
The biosynthesis of atropine starting from l-phenylalanine first undergoes a transamination forming phenylpyruvic acid which is then reduced to phenyl-lactic acid. Coenzyme A then couples phenyl-lactic acid with tropine forming littorine, which then undergoes a radical rearrangement initiated with a P450 enzyme forming hyoscyamine aldehyde. A dehydrogenase then reduces the aldehyde to a primary alcohol making (−)-hyoscyamine, which upon racemization forms atropine. Name
The species name "belladonna" (beautiful woman in Italian) comes from the original use of deadly nightshade to dilate the pupils of the eyes for cosmetic effect. Both atropine and the genus name for deadly nightshade derive from Atropos, one of the three Fates who, according to Greek mythology, chose how a person was to die. See also
Apoatropine
Mark I Nerve Agent Antidote Kit

References
External links
 Media related to Atropine at Wikimedia Commons
"Atropine". Drug Information Portal. U.S. National Library of Medicine. "Atropine sulfate". Drug Information Portal. U.S. National Library of Medicine.