Pharmacodynamics
Scopolamine is a nonspecific muscarinic antagonist at all four muscarinic acetylcholine receptors (M1, M2, M3, and M4).,

Biosynthesis in plants
Scopolamine is among the secondary metabolites of plants from Solanaceae (nightshade) family of plants, such as henbane (Hyoscyamus niger), jimson weed (Datura), angels trumpets (Brugmansia), deadly nightshade (Belladonna), mandrake (Mandragora officinarum), and corkwood (Duboisia). The biosynthesis of scopolamine begins with the decarboxylation of L-ornithine to putrescine by ornithine decarboxylase. Putrescine is methylated to N-methylputrescine by putrescine N-methyltransferase.A putrescine oxidase that specifically recognizes methylated putrescine catalyzes the deamination of this compound to 4-methylaminobutanal, which then undergoes a spontaneous ring formation to N-methyl-pyrrolium cation. In the next step, the pyrrolium cation condenses with acetoacetic acid yielding hygrine. No enzymatic activity could be demonstrated to catalyze this reaction. Hygrine further rearranges to tropinone.Subsequently, tropinone reductase I converts tropinone to tropine, which condenses with phenylalanine-derived phenyllactate to littorine. A cytochrome P450 classified as Cyp80F1 oxidizes and rearranges littorine to hyoscyamine aldehyde. In the final step, hyoscyamine undergoes epoxidation catalyzed by 6beta-hydroxyhyoscyamine epoxidase yielding scopolamine. History
One of the earlier alkaloids isolated from plant sources, scopolamine has been in use in its purified forms (such as various salts, including hydrochloride, hydrobromide, hydroiodide, and sulfate), since its isolation by the German scientist Albert Ladenburg in 1880, and as various preparations from its plant-based form since antiquity and perhaps prehistoric times.
The Hospital Clínic in Barcelona introduced a protocol in 2008 to help medical workers identify cases, while Madrid hospitals adopted a similar working document in February 2015. Hospital Clínic has found little scientific evidence to support this use and relies on the victims stories to reach any conclusion. Although poisoning by scopolamine appears quite often in the media as an aid for raping, kidnapping, killing, or robbery, the effects of this drug and the way it is applied by criminals (transdermal injection, on playing cards and papers, etc.) are often exaggerated, especially skin exposure, as the dose that can be absorbed by the skin is too low to have any effect. Scopolamine transdermal patches must be used for hours to days. There are certain other aspects of the usage of scopolamine in crimes. Powdered scopolamine is referred to as "devils breath". In popular media and television, it is portrayed as a method to brainwash or control people into being defrauded by their attackers; There is debate whether these claims are true. It is not verified if the powdered form is capable of inducing a suggestive state. The danger is real enough that in addition of  Overseas Security Advisory Council (OSAC) in 2012, the US Department of State, as well as the Government of Canada published Travel Advisory too, issued advisory warning travelers about the possibility of targeting. Criminals using Devil’s Breath often use attractive, young women to target men that they believe are wealthy.