Absinthe: what's your poison? Though absinthe is intriguing, it is alcohol in general we should worry about

Visiting the 'green fairy': Absinthe-tourism - A potential challenge for travel medicine?

Increasingly, travellers are looking for novel and unusual tourism experiences. Local produce, such as wine and food, has long been a strong visitor magnet. The search for pleasurable experiences has extended to substances that may be illegal at home, or to those surrounded by mystery. Travel medicine needs to be aware of new trends in tourism, especially if they involve substances with potential health risks, so that appropriate travel health advice can be given including the consideration of potential adverse reactions with current medications or pre-existing conditions. This article introduces a relatively new trend, 'absinthe-tourism', the mysterious drink itself, its flamboyant history and the escalating health issues in the 19th century that finally led to its ban in many countries. Absinthe is now freely available from reputable distilleries. Today, medical concern lies rather with unscrupulous suppliers on the internet, high alcohol content and adulterations. Until evidence suggests otherwise, there may be no concern for healthy travellers on the 'fairy-trail'.

A GABA Interneuron Deficit Model of the Art of Vincent van Gogh

Vincent van Gogh was one of the most influential artists of the Western world, having shaped the post-impressionist art movement by shifting its boundaries forward into abstract expressionism. His distinctive style, which was not valued by the art-buying public during his lifetime, is nowadays one of the most sought after. However, despite the great deal of attention from academic and artistic circles, one important question remains open: was van Gogh's original style a visual manifestation distinct from his troubled mind, or was it in fact a by-product of an impairment that resulted from the psychiatric illness that marred his entire life? In this paper, we use a previously published multi-scale model of brain function to piece together a number of disparate observations about van Gogh's life and art. In particular, we first quantitatively analyze the brushwork of his large production of self-portraits using the image autocorrelation and demonstrate a strong association between the contrasts in the paintings, the occurrence of psychiatric symptoms, and his simultaneous use of absinthe-a strong liquor known to affect gamma aminobutyric acid (GABA) alpha receptors. Secondly, we propose that van Gogh suffered from a defective function of parvalbumin interneurons, which seems likely given his family history of schizophrenia and his addiction to substances associated with GABA action. This could explain the need for the artist to increasingly amplify the contrasts in his brushwork as his disease progressed, as well as his tendency to merge esthetic and personal experiences into a new form of abstraction.

A Systematic Review of Essential Oils and the Endocannabinoid System: A Connection Worthy of Further Exploration

Aromatic compounds have a long history of use as medicines in most recorded cultures. An increasing interest in these therapeutic volatile molecules in both scientific and lay communities has led to the advancement of essential oils as phytomedicines. Recent discoveries suggest essential oils augment the endocannabinoid system in a positive manner to mitigate various pathologies. However, the exact mechanisms whereby essential oils influence endocannabinoid system activity are not fully known, these studies provide a glimpse into their involvement and warrant further evaluation. Additional study of the interaction between essential oils and the endocannabinoid system may lead to promising phytomedicines for the treatment of diseases and conditions involving dysregulation or activation of the endocannabinoid system.

Identification and Quantification of Thujone in a Case of Poisoning Due to Repeated Ingestion of an Infusion of Artemisia Vulgaris L

Plants of the Artemisia genus are used worldwide as ingredients of botanical preparations. This paper describes the case of a 49-year-old man admitted to the emergency room at a Zurich hospital in a manic state after the ingestion of 1 L of an infusion of Artemisia vulgaris. Two monoterpenic ketones, α- and β-thujone, are present in various concentrations in Artemisia spp., but adverse effects have previously been associated only with essential oil from Artemisia absinthium and attributed to the inhibition of gamma-aminobutyric acid receptors, with consequent excitation and convulsions. The aim of this work was to examine and quantify the possible presence of thujone in the patient's serum and urine. A High Performance Liquid Chromatography (HPLC) method with isocratic separation and fluorescence detection (FLD) was set up and validated. Serum thujone concentrations were found to be 27.7 ± 3.48 μg/mL at day 0 and 24.1 ± 0.15 μg/mL on day 1. Results were confirmed by a gas chromatography with flame ionization detection (FID). Poisoning due to thujone was thus confirmed, suggesting four possible scenarios: (1) an unusually high concentration of thujone in the A. vulgaris ingested; (2) chronic exposure as the cause of the poisoning; (3) low metabolic efficiency of the patient; (4) contamination or adulteration of the plant material with other Artemisia spp., for example, A. absinthium.

PRACTICAL APPLICATION

These results could aid research in the field of adverse effects of botanicals, lead to better understanding and management of similar cases of poisoning, and promote more informed use of natural products.

Toxicokinetics of α-thujone following intravenous and gavage administration of α-thujone or α- and β-thujone mixture in male and female F344/N rats and B6C3F1 mice

Plants containing thujone have widespread use and hence have significant human exposure. α-Thujone caused seizures in rodents following gavage administration. We investigated the toxicokinetics of α-thujone in male and female F344/N rats and B6C3F1 mice following intravenous and gavage administration of α-thujone or a mixture of α- and β-thujone (which will be referred to as α,β-thujone). Absorption of α-thujone following gavage administration was rapid without any dose-, species-, sex- or test article-related effect. Absolute bioavailability of α-thujone following administration of α-thujone or α,β-thujone was generally higher in rats than in mice. In rats, females had higher bioavailability than males following administration of either test article although a sex difference was not observed in mice. Cmax and AUC∞ increased greater than proportional to the dose in female rats following administration of α-thujone and in male and female mice following administration of α,β-thujone suggesting possible saturation of elimination kinetics with increasing dose. Dose-adjusted AUC∞ for male and female rats was 5- to 15-fold and 3- to 24-fold higher than mice counterparts following administration of α-thujone and α,β-thujone, respectively (p-value<0.0001 for all comparisons). Following both intravenous and gavage administration, α-thujone was distributed to the brains of rats and mice with females, in general, having higher brain:plasma ratios than males. These data are in support of the observed toxicity of α-thujone and α,β-thujone where females were more sensitive than males of both species to α-thujone-induced neurotoxicity. In general there was no difference in toxicokinetics between test articles when normalized to α-thujone concentration.

Wormwood (Artemisia absinthium L.)--a curious plant with both neurotoxic and neuroprotective properties?

The medical use of the wormwood plant Artemisia absinthium L. dates back to at least Roman times, while during the last century this tradition was seemingly on the decline due to fears of absinthism, a syndrome allegedly caused by the wormwood-flavoured spirit absinthe and more specifically as a result of thujone, a monoterpene ketone often present in the essential oil of wormwood. If threshold concentrations are exceeded, thujone does in fact exhibit neurotoxic properties leading to dose-dependent tonic-clonic seizures in animals, likely caused by GABA type A receptor modulation. Research has shown that the concentrations of thujone present in absinthe were not sufficient to exceed these thresholds, and the marketing of wormwood-flavoured alcoholic beverages has ultimately been reinstated. The declining fears of absinthism may have led to a revival of the medical uses of wormwood, evidenced by several experimental reports, e.g. on the treatment of Crohn's disease. Most recently in this journal, neuroprotective properties of wormwood were detected in rats, and the plant was suggested to be possibly beneficial in the treatment of strokes. While these results sound promising and worthwhile for further investigation, the well-defined profile of adverse properties of wormwood demands a more cautious interpretation of these results. It remained unclear in the studies, for example, if the threshold dose for thujone (e.g. as set by the European Medicines Agency) would be exceeded during therapeutic usage. Due to the colourful history of wormwood, its application in humans should be preceded by a thorough and careful risk-benefit analysis.

Long-term stability of thujone, fenchone, and pinocamphone in vintage preban absinthe

Research was conducted to ascertain whether analyses of vintage absinthe samples represent their original composition in the early 1900s. Absinthe stored in traditional green glass bottles and irradiated with ultraviolet light for up to 200 h exhibited unchanged composition. Samples stored in clear glass exhibited an 18% reduction in beta-thujone content and a concurrent decoloration. These experiments indicate the stability of thujone in vintage absinthes, as these were stored in green glass bottles. The preserved color of the preban absinthes subjected to analysis indicates that no significant light exposure occurred throughout the duration of storage, and therefore provides indirect proof that no loss of terpenes occurred. The stability of absinthe was further demonstrated through the reanalysis of samples from 2001-2005, which exhibited no changes in thujone content as of 2008. A previous evaluation of preban absinthe was therefore valid and not confounded by significant thujone deterioration over time.

Chemical composition of vintage preban absinthe with special reference to thujone, fenchone, pinocamphone, methanol, copper, and antimony concentrations

Thirteen samples of authentic absinthe dating from the preban era (i.e., prior to 1915) were analyzed for parameters that were hypothesized as contributing to the toxicity of the spirit, including naturally occurring herbal essences (thujone, pinocamphone, fenchone), methanol, higher alcohols, copper, and antimony. The total thujone content of preban absinthe was found to range between 0.5 and 48.3 mg/L, with an average concentration of 25.4 +/- 20.3 mg/L and a median concentration of 33.3 mg/L. The authors conclude that the thujone concentration of preban absinthe was generally overestimated in the past. The analysis of postban (1915-1988) and modern commercial absinthes (2003-2006) showed that the encompassed thujone ranges of all absinthes are quite similar, disproving the supposition that a fundamental difference exists between preban and modern absinthes manufactured according to historical recipes. Analyses of pinocamphone, fenchone, base spirits, copper, and antimony were inconspicuous. All things considered, nothing besides ethanol was found in the absinthes that was able to explain the syndrome "absinthism".

Herbal drugs of abuse: an emerging problem

Some herbal products are emerging as popular drugs for recreational abuse. Plant and herbal supplements used recreationally can have a wide spectrum of clinical effects ranging from euphoric and stimulant effects to hallucinogenic experiences. Despite the potential for abuse, addiction, and serious adverse effects, there may be a false perception that these products are all safe, legal, and organic. These perceptions and the ease of accessibility to herbal products could result in greater potential for recreational abuse and subsequent complications presenting to emergency departments. Health care professionals must be cognizant of this emerging problem as increased media coverage and marketing have made these products accessible and recognizable to many young adults and teenagers.

Electrocardiographic findings after acute absinthe intoxication

A 29-year-old comatose patient was brought to Emergency Department with severe alcohol intoxication. No risk factors or cardiac abnormalities were documented. The analysis was negative for other drugs. Plasma electrolyte and cardiac enzymes were normal. The electrocardiogram showed Mobitz type-I atrioventricular block that developed to a rapid junctional rhythm. The patient was stabilized and recovered completely, electrocardiogram then showed sinus rhythm. He admitted important absinthe consumption. Although tachyarrhythmias are frequently developed in acute alcohol intoxication, bradyarrhythmias are exceptional in this context. We present a Wenckebach-type atrioventricular-block in severe alcohol intoxication with absinthe that developed to a rapid junctional rhythm, never described before.

Absinthe—A Review

The alcoholic beverage absinthe is recently experiencing a revival after a yearlong prohibition. This review article provides information on all aspects of this bitter spirit and its major components, especially wormwood (Artemisia absinthium L.), which contains the toxic monoterpene thujone. Over 100 references on historic and current literature are provided. The topics comprise the history of the alcoholic drink starting from its invention in the eighteenth century. Historical and modern recipes are discussed in the context of different quality categories and possibilities to reduce the content of thujone are given. The analytical techniques used to verify compliance with the maximum limit of thujone as well as further possibilities for quality control of absinthe are discussed. The toxicology of absinthe is reviewed with regard to the cause of a syndrome called "absinthism," which was described after chronic abuse of the spirit in the nineteenth century. Finally, a food regulatory and food chemical evaluation is provided and minimum requirements for absinthe are suggested. Absinthe should have a recognizable wormwood flavor and after dilution with water the characteristic clouding should arise (louche-effect). Products, which are advertized as being of premium grade should be made by distillation, should have an alcoholic strength of at least 45%vol, and should not contain artificial dye.

Absinthism: a fictitious 19th century syndrome with present impact

Absinthe, a bitter spirit containing wormwood (Artemisia absinthium L.), was banned at the beginning of the 20th century as consequence of its supposed unique adverse effects. After nearly century-long prohibition, absinthe has seen a resurgence after recent de-restriction in many European countries. This review provides information on the history of absinthe and one of its constituent, thujone. Medical and toxicological aspects experienced and discovered before the prohibition of absinthe are discussed in detail, along with their impact on the current situation. The only consistent conclusion that can be drawn from those 19th century studies about absinthism is that wormwood oil but not absinthe is a potent agent to cause seizures. Neither can it be concluded that the beverage itself was epileptogenic nor that the so-called absinthism can exactly be distinguished as a distinct syndrome from chronic alcoholism.The theory of a previous gross overestimation of the thujone content of absinthe may have been verified by a number of independent studies. Based on the current available evidence, thujone concentrations of both pre-ban and modern absinthes may not have been able to cause detrimental health effects other than those encountered in common alcoholism. Today, a questionable tendency of absinthe manufacturers can be ascertained that use the ancient theories of absinthism as a targeted marketing strategy to bring absinthe into the spheres of a legal drug-of-abuse. Misleading advertisements of aphrodisiac or psychotropic effects of absinthe try to re-establish absinthe's former reputation. In distinction from commercially manufactured absinthes with limited thujone content, a health risk to consumers is the uncontrolled trade of potentially unsafe herbal products such as absinthe essences that are readily available over the internet.

Thujone—Cause of absinthism?

Habitual abuse of the wormwood spirit absinthe was described in the 19th and 20th centuries as a cause for the mental disorder "absinthism" including the symptoms hallucinations, sleeplessness and convulsions. A controversial discussion is going on if thujone, a characteristic component of the essential oil of the wormwood plant Artemisia absinthium L., is responsible for absinthism, or if it was merely caused by chronic alcohol intoxication or by other reasons such as food adulterations. To ascertain if thujone may have caused absinthism, absinthes were produced according to historic recipes of the 19th century. Commercial wormwood herbs of two different manufacturers, as well as self-cultivated ones, were used in a concentration of 6 kg/100 l spirit. In addition, an authentic vintage Pernod absinthe from Tarragona (1930), and two absinthes from traditional small distilleries of the Swiss Val-de-Travers were evaluated. A GC-MS procedure was applied for the analysis of alpha- and beta-thujone with cyclodecanone as internal standard. The method was shown to be sensitive with a LOD of 0.08 mg/l. The precision was between 1.6 and 2.3%, linearity was obtained from 0.1 to 40 mg/l (r = 1.000). After the recent annulment of the absinthe prohibition all analysed products showed a thujone concentration below the maximum limit of 35 mg/l, including the absinthes produced according to historic recipes, which did not contain any detectable or only relatively low concentrations of thujone (mean: 1.3 +/- 1.6 mg/l, range: 0-4.3 mg/l). Interestingly, the vintage absinthe also showed a relatively low thujone concentration of 1.8 mg/l. The Val-de-Travers absinthes contained 9.4 and 1.7 mg/l of thujone. In conclusion, thujone concentrations as high as 260 mg/l, reported in the 19th century, cannot be confirmed by our study. With regard to their thujone concentrations, the hallucinogenic potential of vintage absinthes can be assessed being rather low because the historic products also comply with today's maximum limits derived to exclude such effects. It may be deduced that thujone plays none, or only a minor role in the clinical picture of absinthism.

Chemically Induced Seizures

Drug- and toxin-associated seizures (DTS) may result from exposure to a wide variety of agents. Most DTS can be managed with supportive care. First-line anticonvulsant therapy should include benzodiazepines, unless agents require a specific antidote. Phenytoin is generally not expected to be useful for DTS and in some instances may be harmful. In this article the authors discuss the pathophysiology of DTS, the potential differential diagnosis, and the clinical presentation. They also review selected agents that cause DTS and provide an overview of how the clinician should approach the management of patients who have DTS.

Drug- and toxin-associated seizures

Drug- and toxin-associated seizures may result from exposure to a wide variety of agents. Obtaining a comprehensive history behind the exposure is generally more helpful than diagnostic testing. Most DTS may be managed with supportive care, including benzodiazepines, except in the case of agents that require a specific intervention or antidote.

Molecular mechanisms of toxicity of important food-borne phytotoxins

At present, there is an increasing interest for plant ingredients and their use in drugs, for teas, or in food supplements. The present review describes the nature and mechanism of action of the phytochemicals presently receiving increased attention in the field of food toxicology. This relates to compounds including aristolochic acids, pyrrolizidine alkaloids, beta-carotene, coumarin, the alkenylbenzenes safrole, methyleugenol and estragole, ephedrine alkaloids and synephrine, kavalactones, anisatin, St. John's wort ingredients, cyanogenic glycosides, solanine and chaconine, thujone, and glycyrrhizinic acid. It can be concluded that several of these phytotoxins cause concern, because of their bioactivation to reactive alkylating intermediates that are able to react with cellular macromolecules causing cellular toxicity, and, upon their reaction with DNA, genotoxicity resulting in tumors. Another group of the phytotoxins presented is active without the requirement for bioactivation and, in most cases, these compounds appear to act as neurotoxins interacting with one of the neurotransmitter systems. Altogether, the examples presented illustrate that natural does not equal safe and that in modern society adverse health effects, upon either acute or chronic exposure to phytochemicals, can occur as a result of use of plant- or herb-based foods, teas, or other extracts.

α-Thujone reduces 5-HT3 receptor activity by an effect on the agonist-induced desensitization

The convulsant effects of alpha-thujone, the psychotropic component of absinthe, were attributed to inhibitory actions at the GABAA receptor. Here, we investigated for the first time the 5-HT3 receptor as a potential site of the psychotropic actions of alpha-thujone. This cation permeable ligand-gated ion channel shows considerable homology to the GABAA receptor. We previously demonstrated that in homomeric assemblies of cloned human 5-HT,A receptor subunits. the endogenous agonist 5-HT induced desensitization via channel blockade. When the 5-HT3 B receptor subunit was co-expressed, the resulting heteromeric assemblies desensitized independent from channel blockade. In the present study, patch-clamp experiments revealed an inhibitory action of alpha-thujone on both homomeric and heteromeric 5-HT3 receptors. This inhibitory action was mediated via channel blockade. However, it was not alpha-thujone itself which blocked the channel. The present experiments suggested that, in homomeric receptors, alpha-thujone enhanced the inherent channel-blocking potency of the natural ligand. 5-HT. In heteromeric receptors, alpha-thujonerecruited an additional channel-blocking component of the agonist. By means of kinetic modeling, we simulated possible mechanisms by which alpha-thuljone decreased the 5-HT-induced responses. It is suggested that alpha-thujone reduced 5-HT3 receptor activity by an effect on mechanisms involved in receptor desensitization, which depend on receptor subunit composition. It remains to be shown if this inhibitory action on serotonergic responses contributes to behavioral effects of alpha-thujone.

THIRTEEN-WEEK REPEATED DOSE TOXICITY STUDY OF WORMWOOD (ARTEMISIA ABSINTHIUM) EXTRACT IN RATS

Wormwood, Artemisia absinthium, is a very bitter plant, and its extract has been used as food additives such as seasonings for food and drinks. A 13-week repeated dose toxicity study of wormwood extract was performed in both sexes of Wistar Hannover (GALAS) rats. Rats were divided into 4 groups consisting of 10 males and 10 females each, and were given water containing 0, 0.125, 0.5, or 2% wormwood extract. All rats had survived at the end of the study, and no changes indicating obvious toxicities that are attributable to the treatment of wormwood extract were observed in the body weights, hematological and serum biochemical examinations, organ weights, and histopathological examinations. Based on the results of the present study, the NOAEL (no-observed-adverse-effect-level) of wormwood extract of Wistar Hannover rats was estimated to be 2% (equivalent to 1.27 g/kg/day in males and 2.06 g/kg/day in females) or more.

Absinthe: enjoying a new popularity among young people?

Absinthe, an alcoholic drink used in certain artistic circles and considered the inspiring muse of many famous artists because it was reputed to stimulate creativity and possess exciting, aphrodisiacal and healing properties, in the past enjoyed enormous popularity so much so that it led to a real collective abuse so causing its prohibition in many countries, is again enjoying a new period of popularity. Also in Italy there is increasing information about the use and abuse of this drink. We received a request to analyse and determine the nature of two samples of alcoholic drinks, obtained by macerating Artemisia absinthium leaves in ethanol. Analyses of extracts by gas chromatography/mass spectrometry (GC/MS) identified beta-thujone, which is responsible for the activity and toxic effects on the CNS of absinthe, in both alcohol samples.

Alpha-thujone (the active component of absinthe): gamma-aminobutyric acid type A receptor modulation and metabolic detoxification

Alpha-thujone is the toxic agent in absinthe, a liqueur popular in the 19th and early 20th centuries that has adverse health effects. It is also the active ingredient of wormwood oil and some other herbal medicines and is reported to have antinociceptive, insecticidal, and anthelmintic activity. This study elucidates the mechanism of alpha-thujone neurotoxicity and identifies its major metabolites and their role in the poisoning process. Four observations establish that alpha-thujone is a modulator of the gamma-aminobutyric acid (GABA) type A receptor. First, the poisoning signs (and their alleviation by diazepam and phenobarbital) in mice are similar to those of the classical antagonist picrotoxinin. Second, a strain of Drosophila specifically resistant to chloride channel blockers is also tolerant to alpha-thujone. Third, alpha-thujone is a competitive inhibitor of [(3)H]ethynylbicycloorthobenzoate binding to mouse brain membranes. Most definitively, GABA-induced peak currents in rat dorsal root ganglion neurons are suppressed by alpha-thujone with complete reversal after washout. alpha-Thujone is quickly metabolized in vitro by mouse liver microsomes with NADPH (cytochrome P450) forming 7-hydroxy-alpha-thujone as the major product plus five minor ones (4-hydroxy-alpha-thujone, 4-hydroxy-beta-thujone, two other hydroxythujones, and 7,8-dehydro-alpha-thujone), several of which also are detected in the brain of mice treated i.p. with alpha-thujone. The major 7-hydroxy metabolite attains much higher brain levels than alpha-thujone but is less toxic to mice and Drosophila and less potent in the binding assay. The other metabolites assayed are also detoxification products. Thus, alpha-thujone in absinthe and herbal medicines is a rapid-acting and readily detoxified modulator of the GABA-gated chloride channel.