Scopolamine (Molecule of the Month for February 2011)
Scopolamine is a tropane alkaloid drug with muscarinic antagonist effects. Scopolamine causes central nervous system depression characterized by amnesia, fatigue and reduction in rapid eye movement sleep. It is among the secondary metabolites of plants from Solanaceae (nightshade) family of plants. Scopolamine exerts its effects by acting as a competitive antagonist at muscarinic acetylcholine receptors, specifically M1 receptors; it is thus classified as an anticholinergic, anti-muscarinic drug. Although scopolamine is often portrayed in the media as a dangerous drug, its anticholinergic properties give it some legitimate medical applications in very minute doses. As an example, in the treatment of motion sickness, the dose, gradually released from a transdermal patch, is only 330 micrograms (µg) per day.
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 pre-historic times. Scopolamine was used from the 1940s to the 1960s to put mothers in labor into a kind of "twilight sleep" that did not stop pain, but merely eliminated the memory of pain by attacking the brain functions responsible for self-awareness and self-control. It was also one of the active ingredients in Asthmador, an over-the-counter smoking preparation marketed in the 1950s and 60's claiming to combat asthma and bronchitis. The use of medical scopolamine/opioid combination preparations for euphoria is uncommon but does exist and can be seen in conjunction with opioid use. Doses of scopolamine by itself near the therapeutic range create euphoria and anxiolysis of anticholinergic origin, similar to that of some first-generation antihistamines and similar drugs. Another separate group of users prefer dangerously high doses, especially in the form of datura preparations, for the deliriant and hallucinogenic effects. The hallucinations produced by scopolamine, in common with other potent anticholinergics, are especially real-seeming, with many users reporting hallucinations such as spiders crawling on walls and ceilings, especially in the dark. While some users find this pleasant, often the experience is not one that the user would want to repeat. An overdose of scopolamine is also exceedingly unpleasant physically, and can be fatal, unlike the effect of other more commonly used hallucinogens. For these reasons, naturally occurring anticholinergics are rarely used for recreational purposes.
Scopolamine poisoning is sometimes reported by the media as method by which people are raped, killed, or robbed, although largely exaggerated in many unfounded rumors. The fictional use of scopolamine as a truth serum is featured in a number of works including Farewell, My Lovely, Where Eagles Dare and The Guns of Navarone. Scopolamine and "Twilight Sleep" were integral to the plot of The X-Files season four episode Unruhe and it was mentioned in the season two episode Red Museum. The drug was used as an interrogation tool during Episode 9 of NBC's Kidnapped. It was also featured in "Smut", a December 2008 episode of Law & Order: Special Victims Unit's tenth season, in which a rapist used scopolamine to prevent the women he raped from resisting him and from forming memories.
Formal Chemical Name (IUPAC)
(–)-(S)-3-hydroxy-2-phenylpropionic acid(1R,2R,4S,7S,9S)-9-methyl-3-oxa-9-azatricyclo[3.3.1.02,4]non-7-yl ester
Update by Karl Harrison
(Molecule of the Month for February 2011 )