Although a thienodiazepine, etizolam is clinically regarded as a benzodiazepine because of its mode of action via the benzodiazepine receptor and directly targeting GABAA allosteric modulator receptors.[5]
Abrupt or rapid discontinuation from etizolam, as with benzodiazepines, may result in the appearance of the benzodiazepine withdrawal syndrome, including rebound insomnia.[16]Neuroleptic malignant syndrome, a rare event in benzodiazepine withdrawal, has been documented in a case of abrupt withdrawal from etizolam.[17] This is particularly relevant given etizolam's short half life relative to benzodiazepines such as diazepam resulting in a more rapid drug level decrease in blood plasma levels.[18]
In a study that compared the effectiveness of etizolam, alprazolam, and bromazepam for the treatment of generalized anxiety disorder, all three drugs retained their effectiveness over 2 weeks, but etizolam became more effective from 2 weeks to 4 weeks.[19] Administering .5 mg etizolam twice daily did not induce cognitive deficits over 3 weeks when compared to placebo.[20]
When multiple doses of etizolam, or lorazepam, were administered to rat neurons, lorazepam caused downregulation of alpha-1 benzodiazepine binding sites (tolerance/dependence), while etizolam caused an increase in alpha-2 benzodiazepine binding sites (reverse tolerance to anti-anxiety effects).[21] Tolerance to the anticonvulsant effects of lorazepam was observed, but no significant tolerance to the anticonvulsant effects of etizolam was observed.[21] Etizolam therefore has a reduced liability to induce tolerance, and dependence, compared with classic benzodiazepines.[21]
Etizolam may represent a possible anxiolytic of choice with reduced liability to produce tolerance and dependence after long-term treatment of anxiety and stress syndromes.[22]
Pharmacology
Etizolam, a thienodiazepine derivative, is absorbed fairly rapidly, with peak plasma levels achieved between 30 minutes and 2 hours. It has a mean elimination half life of about 3.4 hours.[4][2][3] Etizolam possesses potent hypnotic properties,[23] and is comparable with other short-acting benzodiazepines.[4] Etizolam acts as a positive allosteric modulator of the GABAA receptor by agonizing the receptor's benzodiazepine site.[24]
According to the Italian prescribing information sheet,[citation needed] etizolam belongs to a new class of diazepines, thienotriazolodiazepines. This new class is easily oxidized, rapidly metabolized, and has a lower risk of accumulation, even after prolonged treatment. Etizolam has an anxiolytic action about 6-8 times greater than that of diazepam. Etizolam produces, especially at higher dosages, a reduction in time taken to fall asleep, an increase in total sleep time, and a reduction in the number of awakenings. During tests, there were no substantial changes in deep sleep; however, it may reduce REM sleep. In EEG tests of healthy volunteers, etizolam showed some similar characteristics to tricyclic antidepressants.[25][26]
Etizolam's main metabolites in humans are alpha-hydroxyetizolam and 8-hydroxyetizolam. alpha-Hydroxyetizolam is pharmacologically active and has a half-life of approximately 8.2 hours.[27]
Interactions
Itraconazole and fluvoxamine slow down the rate of elimination of etizolam, leading to accumulation of etizolam, therefore increasing its pharmacological effects.[28][29]Carbamazepine speeds up the metabolism of etizolam, resulting in reduced pharmacological effects.[30]
Cases of intentional suicide by overdose using etizolam in combination with GABA agonists have been reported.[27][31] Although etizolam has a lower LD50 than certain benzodiazepines, the LD50 is still far beyond the prescribed or recommended dose. Flumazenil, a GABA antagonist agent used to reverse benzodiazepine overdoses, inhibits the effect of etizolam as well as classical benzodiazepines such as diazepam and chlordiazepoxide.[32]
Etizolam overdose deaths are rising - for instance, the National Records of Scotland report on drug-related deaths, 'street' Etizolam was a factor in ("implicated in, or potentially contributed to") 752, or 59%, of drug-related deaths in Scotland in 2019. It is important to highlight that more than one drug contributed to the vast majority of the deaths (by way of comparison, opiates and opioids were a factor in 1092, or 86%, of drug-related deaths).[33]
Society and culture
Brand names
Etilaam, Sedekopan, Etizest, Etizex, Pasaden or Depas
In India, it is a Narcotics prescription-only (NRx) medication used for anxiety disorders, sometimes in combination with other drugs, i.e. the beta blockerpropranolol.
Etizolam is not authorized by the FDA for medical use in the U.S. As of March 2016, etizolam is a controlled substance in the following states: Alabama,[44] Arkansas,[45] Florida,[46] Georgia (as Schedule IV, whereas all other states listed here prohibit it as a Schedule I substance), Louisiana, Mississippi,[47] Texas,[48] South Carolina,[49] and Virginia.[50] It is controlled in Indiana as of July 1, 2017.[51] It is controlled in Ohio as of February 2018.
On December 23, 2022, the DEA announced it had begun consideration on the matter of placing Etizolam under temporary Schedule I status.[52]
Later on July 25, 2023, the DEA published a pre-print notice that Etizolam would become temporarily scheduled as a Schedule I controlled substance from 26 July 2023 to 26 July 2025.[53]
Etizolam is a drug of potential misuse. Cases of etizolam dependence have been documented in the medical literature.[54] Since 1991, cases of etizolam misuse and addiction have substantially increased,[55] due to varying levels of accessibility and cultural popularity.[56] Pills being sold as Xanax or other benzodiazepines that are illicitly manufactured may often contain etizolam rather than their listed ingredient [57][37]
^ abcFracasso C, Confalonieri S, Garattini S, Caccia S (1991-02-01). "Single and multiple dose pharmacokinetics of etizolam in healthy subjects". European Journal of Clinical Pharmacology. 40 (2): 181–185. doi:10.1007/BF00280074. PMID2065698. S2CID10176681.
^ abSanna E, Pau D, Tuveri F, Massa F, Maciocco E, Acquas C, et al. (February 1999). "Molecular and neurochemical evaluation of the effects of etizolam on GABAA receptors under normal and stress conditions". Arzneimittel-Forschung. 49 (2): 88–95. doi:10.1055/s-0031-1300366. PMID10083975. S2CID19732765.
^Lopedota A, Cutrignelli A, Trapani A, Boghetich G, Denora N, Laquintana V, et al. (May 2007). "Effects of different cyclodextrins on the morphology, loading and release properties of poly (DL-lactide-co-glycolide)-microparticles containing the hypnotic agent etizolam". Journal of Microencapsulation. 24 (3): 214–24. doi:10.1080/02652040601058152. PMID17454433. S2CID31434550.
^Hirase M, Ishida T, Kamei C (November 2008). "Rebound insomnia induced by abrupt withdrawal of hypnotics in sleep-disturbed rats". European Journal of Pharmacology. 597 (1–3): 46–50. doi:10.1016/j.ejphar.2008.08.024. PMID18789918.
^Bertolino A, Mastucci E, Porro V, Corfiati L, Palermo M, Ecari U, Ceccarelli G (25 June 2016). "Etizolam in the treatment of generalized anxiety disorder: a controlled clinical trial". The Journal of International Medical Research. 17 (5): 455–60. doi:10.1177/030006058901700507. PMID2572494. S2CID43179840.
^De Candia MP, Di Sciascio G, Durbano F, Mencacci C, Rubiera M, Aguglia E, et al. (December 2009). "Effects of treatment with etizolam 0.5 mg BID on cognitive performance: a 3-week, multicenter, randomized, double-blind, placebo-controlled, two-treatment, three-period, noninferiority crossover study in patients with anxiety disorder". Clinical Therapeutics. 31 (12): 2851–9. doi:10.1016/j.clinthera.2009.12.010. PMID20110024.
^ abcSanna E, Busonero F, Talani G, Mostallino MC, Mura ML, Pisu MG, et al. (September 2005). "Low tolerance and dependence liabilities of etizolam: molecular, functional, and pharmacological correlates". European Journal of Pharmacology. 519 (1–2): 31–42. doi:10.1016/j.ejphar.2005.06.047. PMID16107249.
^Sanna E, Busonero F, Talani G, Mostallino MC, Mura ML, Pisu MG, et al. (September 2005). "Low tolerance and dependence liabilities of etizolam: molecular, functional, and pharmacological correlates". European Journal of Pharmacology. 519 (1–2): 31–42. doi:10.1016/j.ejphar.2005.06.047. PMID16107249.
^Nakamura J, Mukasa H (December 1992). "Effects of thienodiazepine derivatives, etizolam and clotiazepam on the appearance of Fm theta". The Japanese Journal of Psychiatry and Neurology. 46 (4): 927–31. doi:10.1111/j.1440-1819.1992.tb02862.x. PMID1363923. S2CID11263866.
^"Etizolam". PubChem. U.S. National Library of Medicine. Retrieved 2020-09-03.
^ abNakamae T, Shinozuka T, Sasaki C, Ogamo A, Murakami-Hashimoto C, Irie W, et al. (November 2008). "Case report: Etizolam and its major metabolites in two unnatural death cases". Forensic Science International. 182 (1–3): e1-6. doi:10.1016/j.forsciint.2008.08.012. PMID18976871.
^Araki K, Yasui-Furukori N, Fukasawa T, Aoshima T, Suzuki A, Inoue Y, et al. (August 2004). "Inhibition of the metabolism of etizolam by itraconazole in humans: evidence for the involvement of CYP3A4 in etizolam metabolism". European Journal of Clinical Pharmacology. 60 (6): 427–30. doi:10.1007/s00228-004-0789-1. PMID15232663. S2CID22970567.
^Suzuki Y, Kawashima Y, Shioiri T, Someya T (December 2004). "Effects of concomitant fluvoxamine on the plasma concentration of etizolam in Japanese psychiatric patients: wide interindividual variation in the drug interaction". Therapeutic Drug Monitoring. 26 (6): 638–42. doi:10.1097/00007691-200412000-00009. PMID15570188. S2CID12164244.
^Kondo S, Fukasawa T, Yasui-Furukori N, Aoshima T, Suzuki A, Inoue Y, et al. (May 2005). "Induction of the metabolism of etizolam by carbamazepine in humans". European Journal of Clinical Pharmacology. 61 (3): 185–8. doi:10.1007/s00228-005-0904-y. PMID15776275. S2CID9612361.
^Høiseth G, Tuv SS, Karinen R (November 2016). "Blood concentrations of new designer benzodiazepines in forensic cases". Forensic Science International. 268: 35–38. doi:10.1016/j.forsciint.2016.09.006. PMID27685473.
^Woolverton WL, Nader MA (December 1995). "Effects of several benzodiazepines, alone and in combination with flumazenil, in rhesus monkeys trained to discriminate pentobarbital from saline". Psychopharmacology. 122 (3): 230–6. doi:10.1007/bf02246544. PMID8748392. S2CID24836734.
^"Gesetz über den Verkehr mit Betäubungsmitteln" [Law on traffic with tranquillizers]. Bundesministerium der Justiz und für Verbraucherschutz (Federal Ministry of Justice and Consumer Protection) (in German).