Atropine is a racemate composed of equimolar concentrations of (S)- and (R)-atropine. It is obtained from deadly nightshade (Atropa belladonna) and other plants of the family Solanaceae. It has a role as a muscarinic antagonist, an anaesthesia adjuvant, an anti-arrhythmia drug, a mydriatic agent, a parasympatholytic, a bronchodilator agent, a plant metabolite, an antidote to sarin poisoning and a oneirogen. It contains a (S)-atropine and a (R)-atropine.