Tag: Benzodiazepine

What is Oxazepam?

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Introduction

Oxazepam is a short-to-intermediate-acting benzodiazepine. Oxazepam is used for the treatment of anxiety, insomnia, and to control symptoms of alcohol withdrawal syndrome.

It is a metabolite of diazepam, prazepam, and temazepam, and has moderate amnesic, anxiolytic, anticonvulsant, hypnotic, sedative, and skeletal muscle relaxant properties compared to other benzodiazepines.

It was patented in 1962 and approved for medical use in 1964.

Medical Uses

Oxazepam is an intermediate-acting benzodiazepine with a slow onset of action, so it is usually prescribed to individuals who have trouble staying asleep, rather than falling asleep. It is commonly prescribed for anxiety disorders with associated tension, irritability, and agitation. It is also prescribed for drug and alcohol withdrawal, and for anxiety associated with depression. Oxazepam is sometimes prescribed off-label to treat social phobia, post-traumatic stress disorder, insomnia, premenstrual syndrome, and other conditions.

Side Effects

The side effects of oxazepam are similar to those of other benzodiazepines, and may include dizziness, drowsiness, headache, memory impairment, paradoxical excitement, and anterograde amnesia, but does not affect transient global amnesia.[citation needed] Withdrawal effects due to rapid decreases in dosage or abrupt discontinuation of oxazepam may include abdominal and muscle cramps, seizures, depression, insomnia, sweating, tremors, or nausea and vomiting.

In September 2020, the US Food and Drug Administration (FDA) required the boxed warning be updated for all benzodiazepine medicines to describe the risks of abuse, misuse, addiction, physical dependence, and withdrawal reactions consistently across all the medicines in the class.

Tolerance, Dependence and Withdrawal

Oxazepam, as with other benzodiazepine drugs, can cause tolerance, physical dependence, addiction, and benzodiazepine withdrawal syndrome. Withdrawal from oxazepam or other benzodiazepines often leads to withdrawal symptoms which are similar to those seen during alcohol and barbiturate withdrawal. The higher the dose and the longer the drug is taken, the greater the risk of experiencing unpleasant withdrawal symptoms. Withdrawal symptoms can occur, though, at standard dosages and also after short-term use. Benzodiazepine treatment should be discontinued as soon as possible by a slow and gradual dose reduction regimen.

Contraindications

Oxazepam is contraindicated in myasthenia gravis, chronic obstructive pulmonary disease, and limited pulmonary reserve, as well as severe hepatic disease.

Special Precautions

Benzodiazepines require special precautions if used in the elderly, during pregnancy, in children, alcohol- or drug-dependent individuals, and individuals with comorbid psychiatric disorders. Benzodiazepines including oxazepam are lipophilic drugs and rapidly penetrate membranes, so rapidly crosses over into the placenta with significant uptake of the drug. Use of benzodiazepines in late pregnancy, especially high doses, may result in floppy infant syndrome.

Pregnancy

Oxazepam, when taken during the third trimester, causes a definite risk to the neonate, including a severe benzodiazepine withdrawal syndrome including hypotonia, reluctance to suck, apnoeic spells, cyanosis, and impaired metabolic responses to cold stress. Floppy infant syndrome and sedation in the newborn may also occur. Symptoms of floppy infant syndrome and the neonatal benzodiazepine withdrawal syndrome have been reported to persist from hours to months after birth.

Interactions

As oxazepam is an active metabolite of diazepam, an overlap in possible interactions is likely with other drugs or food, with exception of the pharmacokinetic CYP450 interactions (e.g. with cimetidine). Precautions and following the prescription are required when taking oxazepam (or other benzodiazepines) in combinations with antidepressants or opioids. Concurrent use of these medications can interact in a way that is difficult to predict. Drinking alcohol when taking oxazepam is not recommended. Concomitant use of oxazepam and alcohol can lead to increased sedation, memory impairment, ataxia, decreased muscle tone, and, in severe cases or in predisposed patients, respiratory depression and coma.

Overdose

Oxazepam is generally less toxic in overdose than other benzodiazepines. Important factors which affect the severity of a benzodiazepine overdose include the dose ingested, the age of the patient, and health status prior to overdose. Benzodiazepine overdoses can be much more dangerous if a coingestion of other CNS depressants such as opiates or alcohol has occurred. Symptoms of an oxazepam overdose include:

  • Respiratory depression
  • Excessive somnolence
  • Altered consciousness
  • Central nervous system depression
  • Occasionally cardiovascular and pulmonary toxicity
  • Rarely, deep coma

Pharmacology

Oxazepam is an intermediate-acting benzodiazepine of the 3-hydroxy family; it acts on benzodiazepine receptors, resulting in increased effect of GABA to the GABAA receptor which results in inhibitory effects on the central nervous system. The half-life of oxazepam is between 6 and 9 hours. It has been shown to suppress cortisol levels. Oxazepam is the most slowly absorbed and has the slowest onset of action of all the common benzodiazepines according to one British study.

Oxazepam is an active metabolite formed during the breakdown of diazepam, nordazepam, and certain similar drugs. It may be safer than many other benzodiazepines in patients with impaired liver function because it does not require hepatic oxidation, but rather, it is simply metabolised by glucuronidation, so oxazepam is less likely to accumulate and cause adverse reactions in the elderly or people with liver disease. Oxazepam is similar to lorazepam in this respect. Preferential storage of oxazepam occurs in some organs, including the heart of the neonate. Absorption by any administered route and the risk of accumulation is significantly increased in the neonate, and withdrawal of oxazepam during pregnancy and breast feeding is recommended, as oxazepam is excreted in breast milk.

Two milligrams of oxazepam equates to 1 mg of diazepam according to the benzodiazepine equivalency converter, therefore 20 mg of oxazepam according to BZD equivalency equates to 10 mg of diazepam and 15 mg oxazepam to 7.5 mg diazepam (rounded up to 8 mg of diazepam). Some BZD equivalency converters use 3 to 1 (oxazepam to diazepam), 1 to 3 (diazepam to oxazepam) as the ratio (3:1 and 1:3), so 15 mg of oxazepam would equate to 5 mg of diazepam.

Chemistry

Oxazepam exists as a racemic mixture. Early attempts to isolate enantiomers were unsuccessful; the corresponding acetate has been isolated as a single enantiomer. Given the different rates of epimerisation that occur at different pH levels, it was determined that there would be no therapeutic benefit to the administration of a single enantiomer over the racemic mixture.

Frequency of Use

Oxazepam, along with diazepam, nitrazepam, and temazepam, were the four benzodiazepines listed on the pharmaceutical benefits scheme and represented 82% of the benzodiazepine prescriptions in Australia in 1990–1991. It is in several countries the benzodiazepine of choice for novice users, due to a low chance of accumulation and a relatively slow absorption speed.

Society and Culture

Misuse

Oxazepam has the potential for misuse, defined as taking the drug to achieve a high, or continuing to take the drug in the long term against medical advice. Benzodiazepines, including diazepam, oxazepam, nitrazepam, and flunitrazepam, accounted for the largest volume of forged drug prescriptions in Sweden from 1982 to 1986. During this time, a total of 52% of drug forgeries were for benzodiazepines, suggesting they were a major prescription drug class of abuse.

However, due to its slow rate of absorption and its slow onset of action, oxazepam has a relatively low potential for abuse compared to some other benzodiazepines, such as temazepam, flunitrazepam, or triazolam. This is similar to the varied potential for abuse between different drugs of the barbiturate class.

Legal Status

Oxazepam is a Schedule IV drug under the Convention on Psychotropic Substances.

Brand Names

Oxazepam is marketed under many brand names worldwide, including: Alepam, Alepan, Anoxa, Anxiolit, Comedormir, durazepam, Murelax, Nozepam, Oksazepam, Opamox, Ox-Pam, Oxa-CT, Oxabenz, Oxamin, Oxapam, Oxapax, Oxascand, Oxaze, Oxazepam, Oxazépam, Oxazin, Oxepam, Praxiten, Purata, Selars, Serax, Serepax, Seresta, Séresta, Serpax, Sobril, Tazepam, Vaben, and Youfei.

It is also marketed in combination with hyoscine as Novalona and in combination with alanine as Pausafrent T.

Environmental Concerns

In 2013, a laboratory study which exposed European perch to oxazepam concentrations equivalent to those present in European rivers (1.8 μg/L) found that they exhibited increased activity, reduced sociality, and higher feeding rate. In 2016, a follow-up study which exposed salmon smolt to oxazepam for seven days before letting them migrate observed increased intensity of migratory behaviour compared to controls. A 2019 study associated this faster, bolder behaviour in exposed smolt to increased mortality due to a higher likelihood of being predated on.

On the other hand, a 2018 study from the same authors, which kept 480 European perch and 12 northern pikes in 12 ponds over 70 days, half of them control and half spiked with oxazepam, found no significant difference in either perch growth or mortality. However, it suggested that the latter could be explained by the exposed perch and pike being equally hampered by oxazepam, rather than the lack of an overall effect. Lastly, a 2021 study built on these results by comparing two whole lakes filled with perch and pikes – one control while the other was exposed to oxazepam 11 days into experiment, at concentrations between 11 and 24 μg/L, which is 200 times greater than the reported concentrations in the European rivers. Even so, there were no measurable effects on pike behaviour after the addition of oxazepam, while the effects on perch behaviour were found to be negligible. The authors concluded that the effects previously attributed to oxazepam were instead likely caused by a combination of fish being stressed by human handling and small aquaria, followed by being exposed to a novel environment.

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What is Nitrazolam?

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Introduction

Nitrazolam is a triazolobenzodiazepine (TBZD) , which are benzodiazepine (BZD) derivatives, that has been sold online as a designer drug.

It is closely related to clonazolam or flunitrazolam, only differing by the removal of a chlorine or fluorine group respectively at the benzene ring.

A study in mice indicated that nitrazolam can be several times more potent than diazepam as an antagonist of electroshock-induced tonic-extensor convulsions but less potent than diazepam at preventing the righting reflex

Nitrazolam has been used as an example compound to demonstrate the microscale synthesis of reference materials utilising polymer‐supported reagents.

Legal Status

United Kingdom

In the UK, nitrazolam has been classified as a Class C drug by the May 2017 amendment to The Misuse of Drugs Act 1971 along with several other designer benzodiazepine drugs.

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What is Imidazopyridine?

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Introduction

An imidazopyridine is a nitrogen containing heterocycle that is also a class of drugs that contain this same chemical substructure. In general, they are GABAA receptor agonists, however recently proton pump inhibitors, aromatase inhibitors, non-steroidal anti-inflammatory drugs (NSAIDs) and other classes of drugs in this class have been developed as well.

Despite usually being similar to them in effect, they are not chemically related to benzodiazepines. As such, GABAA-agonising imidazopyridines, pyrazolopyrimidines, and cyclopyrrones are sometimes grouped together and referred to as “nonbenzodiazepines.”

Imidazopyridines include the following.

Sedatives

Anxiolytics, sedatives and hypnotics (GABAA receptor positive allosteric modulators):

  • Imidazo[1,2-a]pyridines:
    • Alpidem (original brand name Ananxyl) – an anxiolytic that was withdrawn from the market worldwide in 1995 due to hepatotoxicity.
    • DS-1—a GABAA receptor positive allosteric modulator selective for the α4β3δ subtype, which is not targeted by other GABAergics such as benzodiazepines or other nonbenzodiazepines.
    • Necopidem—an anxiolytic. It has not found clinical use.
    • Saripidem—a sedative and anxiolytic. It is not used clinically.
    • TP-003—a subtype-selective partial agonist at GABAA receptors, binding to GABAA receptor complexes bearing either α2, α3 or α5 subunits, but only showing significant efficacy at α3.
    • Zolpidem (original brand name Ambien)—a widely used hypnotic. Generic versions are widely available.
  • Imidazo[4,5-c]pyridines:
    • Bamaluzole—a GABAA receptor-agonising anticonvulsant that was never marketed.

Antipsychotic

Antipsychotics:

Gastrointestinal

Drugs used for peptic ulcer disease (PUD), GERD and gastroprokinetic agents (motility stimulants):

  • Imidazo[1,2-a]pyridines:
    • CJ-033466—an experimental gastroprokinetic acting as a selective 5-HT4 serotonin receptor partial agonist.
    • Zolimidine—a gastroprotective agent.
    • Linaprazan—a potassium-competitive acid blocker which demonstrated similar efficacy as esomeprazole in healing and controlling symptoms of GERD patients with erosive esophagitis.
    • SCH28080—the prototypical potassium-competitive acid blocker which has not found clinical use because of liver toxicity in animal trials and elevated liver enzyme activity in the serum of human volunteers.
  • Imidazo[4,5-b]pyridines:
    • Tenatoprazole—it blocks the gastric proton pump leading to decline of gastric acid production.

Anti-Inflammatories

NSAIDs, analgesics and antimigraine drugs:

  • Imidazo[1,2-a]pyridines:
    • Miroprofen—a derivative of propionic acid.
  • Imidazo[4,5-b]pyridines:
    • Telcagepant—a calcitonin gene-related peptide receptor antagonist which was in clinical trials as a remedy for migraine. Its development was terminated.

Cardiovascular

Drugs acting on the cardiovascular system:

  • Imidazo[1,2-a]pyridines:
    • Olprinone (loprinone) – a cardiac stimulant.

Bone

Drugs for treatment of bone diseases:

  • Imidazo[1,2-a]pyridines:
    • Minodronic acid (brand names Bonoteo, Recalbon)—a third-generation bisphosphonate used for the treatment of osteoporosis.

Antineoplastic

Antineoplastic agents:

  • Imidazo[1,5-a]pyridines:
    • Fadrozole (brand name Afema)—an aromatase inhibitor.
  • Imidazo[4,5-c]pyridines:
    • 3-Deazaneplanocin A—an S-adenosyl-L-homocysteine synthesis inhibitor and histone methyltransferase EZH2 inhibitor.

Antiviral

Directly-acting antiviral agents:

  • Imidazo[1,2-a]pyridines:
    • Tegobuvir (GS-9190) – an allosteric, non-nucleoside hepatitis C virus NS5B RNA-dependent RNA polymerase inhibitor targeting the thumb II allosteric site.

DAergic

  • PIP3EA [885446-91-3] D4 agonist supported to have penile erectant properties.

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What is Medazepam?

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Introduction

Medazepam is a drug that is a benzodiazepine derivative. It possesses anxiolytic, anticonvulsant, sedative, and skeletal muscle relaxant properties. It is known by the following brand names: Azepamid, Nobrium, Tranquirax (mixed with bevonium), Rudotel, Raporan, Ansilan and Mezapam. Medazepam is a long-acting benzodiazepine drug. The half-life of medazepam is 36–200 hours.

Pharmacology

Medazepam acts as a prodrug to diazepam, as well as nordazepam, temazepam and oxazepam. Benzodiazepine drugs including medazepam increase the inhibitory processes in the cerebral cortex by allosteric modulation of the GABA receptor. Benzodiazepines may also act via micromolar benzodiazepine-binding sites as Ca2+ channel blockers and significantly inhibited depolarisation-sensitive calcium uptake in experiments with cell components from rat brains. This has been conjectured as a mechanism for high dose effects against seizures in a study. It has major active benzodiazepine metabolites, which gives it a more prolonged therapeutic effect after administration.

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What is Meclonazepam?

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Introduction

Meclonazepam-3-methylclonazepam) was discovered by a team at Hoffmann-La Roche in the 1970s and is a drug which is a benzodiazepine derivative similar in structure to clonazepam. It has sedative and anxiolytic actions like those of other benzodiazepines, and also has anti-parasitic effects against the parasitic worm Schistosoma mansoni.

Meclonazepam was never used as medicine and instead appeared online as a designer drug.

Legal Issues

United Kingdom

In the UK, meclonazepam has been classified as a Class C drug by the May 2017 amendment to The Misuse of Drugs Act 1971 along with several other designer benzodiazepine drugs.

This page is based on the copyrighted Wikipedia article < https://en.wikipedia.org/wiki/Meclonazepam >; it is used under the Creative Commons Attribution-ShareAlike 3.0 Unported License (CC-BY-SA). You may redistribute it, verbatim or modified, providing that you comply with the terms of the CC-BY-SA.

What is Etizolam?

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Introduction

Etizolam (marketed under many brand names) is a thienodiazepine derivative which is a benzodiazepine analogue. The etizolam molecule differs from a benzodiazepine in that the benzene ring has been replaced by a thiophene ring and triazole ring has been fused, making the drug a thienotriazolodiazepine.

Although a thienodiazepine, etizolam is clinically regarded as a benzodiazepine because of its mode of action via the benzodiazepine receptor and directly targeting GABAA receptors.

It possesses anxiolytic, amnesic, anticonvulsant, hypnotic, sedative and skeletal muscle relaxant properties. Etizolam is an anxiolytic found to have lower tolerance and dependence liability than benzodiazepines.

It was patented in 1972 and approved for medical use in 1983.

As of April 2021, the export of Etizolam has been banned in India.

Medical Uses

  • Short-term treatment of insomnia.
  • Anxiety disorders such as obsessive compulsive disorder (OCD) and general anxiety disorder (GAD), mostly as a short-term medication to be used purely on an at-need basis

Side Effects

Long term use may result in blepharospasms, especially in women. Doses of 4 mg or more may cause anterograde amnesia.

In rare cases, erythema annulare centrifugum skin lesions have resulted.

Tolerance, Dependence and Withdrawal

Abrupt or rapid discontinuation from etizolam, as with benzodiazepines, may result in the appearance of the benzodiazepine withdrawal syndrome, including rebound insomnia. Neuroleptic malignant syndrome, a rare event in benzodiazepine withdrawal, has been documented in a case of abrupt withdrawal from etizolam. 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.

In a study that compared the effectiveness of etizolam, alprazolam, and bromazepam for the treatment of GAD, all three drugs retained their effectiveness over 2 weeks, but etizolam became more effective from 2 weeks to 4 weeks. Administering .5 mg etizolam twice daily did not induce cognitive deficits over 3 weeks when compared to placebo.

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). Tolerance to the anticonvulsant effects of lorazepam was observed, but no significant tolerance to the anticonvulsant effects of etizolam was observed. Etizolam therefore has a reduced liability to induce tolerance, and dependence, compared with classic benzodiazepines.

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.

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. Etizolam possesses potent hypnotic properties, and is comparable with other short-acting benzodiazepines. Etizolam acts as a positive allosteric modulator of the GABAA receptor by agonising the receptor’s benzodiazepine site.

According to the Italian prescribing information sheet, 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.

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.

Interactions

Itraconazole and fluvoxamine slow down the rate of elimination of etizolam, leading to accumulation of etizolam, therefore increasing its pharmacological effects. Carbamazepine speeds up the metabolism of etizolam, resulting in reduced pharmacological effects.

Overdose

Refer to Benzodiazepine Overdose.

Cases of intentional suicide by overdose using etizolam in combination with GABA agonists have been reported. 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.

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).

Society and Culture

Brand Names

Etilaam, Sedekopan, Etizest, Etizex, Pasaden or Depas

Legal Status

International Drug Control Conventions

On 13 December 2019, the World Health Organisation recommended Etizolam be placed in Schedule 4 of the 1971 Convention on Psychotropic Substances. This recommendation was followed by the placement of Etizolam into Schedule IV in March 2020.

Australia

Etizolam is not used medically in Australia but has been found in counterfeit Xanax pills.

Denmark

Etizolam is controlled in Denmark under the Danish Misuse of Drugs Act.

Germany

Etizolam was controlled in Germany in July 2013 but is not used medically.

Italy

Etizolam is licensed for the treatment of anxiety, insomnia and neurosis as a prescription-only medication.

India

In India, it is a prescription-only medication used for anxiety disorders, sometimes in combination with other drugs like propranolol.

United Kingdom

In the UK, etizolam has been classified as a Class C drug by the May 2017 amendment to The Misuse of Drugs Act 1971 along with several other designer benzodiazepine drugs.

United States

Etizolam is not authorised by the FDA for medical use in the U.S. However, it currently remains unscheduled at the federal level and is legal for research purposes as of March 2020. As of March 2016, etizolam is a controlled substance in the following states: Alabama, Arkansas, Florida, Georgia (as Schedule IV, whereas all other states listed here prohibit it as a Schedule I substance), Louisiana, Mississippi, Texas, South Carolina, and Virginia. It is controlled in Indiana as of 01 July 2017. It is controlled in Ohio as of February 2018. On 23 December 2022 the DEA announced it had begun consideration on the matter of placing Etizolam under temporary Schedule I status.

Misuse

Etizolam is a drug of potential misuse. Cases of etizolam dependence have been documented in the medical literature. However, conflicting reports from the World Health Organisation, made public in 1991, dispute the misuse claims. Since 1991, cases of etizolam misuse and addiction have substantially increased, due to varying levels of accessibility and cultural popularity. Pills being sold as Xanax or other benzodiazepines that are illicitly manufactured may often contain etizolam rather than their listed ingredient.

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What is Clorazepate?

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Introduction

Clorazepate, sold under the brand name Tranxene among others, is a benzodiazepine medication. It possesses anxiolytic, anticonvulsant, sedative, hypnotic, and skeletal muscle relaxant properties. Clorazepate is an unusually long-lasting benzodiazepine and serves as a majoritive prodrug for the equally long-lasting desmethyldiazepam, which is rapidly produced as an active metabolite. Desmethyldiazepam is responsible for most of the therapeutic effects of clorazepate.

It was patented in 1965 and approved for medical use in 1967.

Medical Uses

Clorazepate is used in the treatment of anxiety disorders and insomnia. It may also be prescribed as an anticonvulsant or muscle relaxant. It is also used as a premedication.

Clorazepate is prescribed principally in the treatment of alcohol withdrawal and epilepsy, although it is also a useful anxiolytic because of its long half-life. The normal starting dosage range of Clorazepate is 15 to 60 mg per day. The drug is to be taken two to four times per day. Dosages as high as 90 to 120 mg per day may be used in the treatment of acute alcohol withdrawal. In the United States and Canada, Clorazepate is available in 3.75, 7.5, and 15 mg capsules or tablets. In Europe, tablet formations are 5 mg, 10 mg, 20 mg and 50 mg. Clorazepate SD (controlled release) is available and may have a reduced incidence of adverse effects. The sustained-release formulation of clorazepate has some advantages in that, if a dose is missed, less profound fluctuations in blood plasma levels occur, which may be helpful to some people with epilepsy at risk of break-through seizures.

Adverse Effects

Adverse effects of clorazepate include tolerance, dependence, withdrawal reactions, cognitive impairment, confusion, anterograde amnesia, falls in the elderly, ataxia, hangover effects, and drowsiness. It is unclear whether cognitive deficits resulting from the long-term use of benzodiazepines return to normal or persist indefinitely after withdrawal from benzodiazepines. Benzodiazepines are also known to cause or worsen depression. Paradoxical effects including excitement and paradoxical worsening of seizures can sometimes result from the use of benzodiazepines. Children, the elderly, individuals with a history of alcohol use disorder or a history of aggressive behaviour and anger are at greater risk of developing paradoxical reactions to benzodiazepines.

In September 2020, the US Food and Drug Administration (FDA) required the boxed warning be updated for all benzodiazepine medicines to describe the risks of non-medical use, addiction, physical dependence, and withdrawal reactions consistently across all the medicines in the class.

Tolerance, Dependence and Withdrawal

Refer to Benzodiazepine Withdrawal Syndrome.

Delirium has been noted from discontinuation from clorazepate. A benzodiazepine dependence occurs in approximately one third of patients who take benzodiazepines for longer than 4 weeks, which is characterised by a withdrawal syndrome upon dose reduction. When used for seizure control, tolerance may manifest itself with an increased rate of seizures as well an increased risk of withdrawal seizures. In humans, tolerance to the anticonvulsant effects of clorazepate occurs frequently with regular use. Due to the development of tolerance, benzodiazepines are, in general, not considered appropriate for the long-term management of epilepsy; increasing the dose may result only in the developing of tolerance to the higher dose combined with worsened adverse effects. Cross-tolerance occurs between benzodiazepines, meaning that, if individuals are tolerant to one benzodiazepine, they will display a tolerance to equivalent doses of other benzodiazepines. Withdrawal symptoms from benzodiazepines include a worsening of pre-existing symptoms as well as the appearance of new symptoms that were not pre-existing. The withdrawal symptoms may range from mild anxiety and insomnia to severe withdrawal symptoms such as seizures and psychosis. Withdrawal symptoms can be difficult in some cases to differentiate between pre-existing symptoms and withdrawal symptoms. Use of high doses, long-term use and abrupt or over-rapid withdrawal increases increase the severity of withdrawal syndrome. However, tolerance to the active metabolite of clorazepate may occur more slowly than with other benzodiazepines. Regular use of benzodiazepines causes the development of dependence characterised by tolerance to the therapeutic effects of benzodiazepines and the development of the benzodiazepine withdrawal syndrome including symptoms such as anxiety, apprehension, tremor, insomnia, nausea, and vomiting upon cessation of benzodiazepine use. Withdrawal from benzodiazepines should be gradual as abrupt withdrawal from high doses of benzodiazepines may cause confusion, toxic psychosis, convulsions, or a condition resembling delirium tremens. Abrupt withdrawal from lower doses may cause depression, nervousness, rebound insomnia, irritability, sweating, and diarrhoea.

Interactions

All sedatives or hypnotics e.g. other benzodiazepines, barbiturates, antiepileptic drugs, alcohol, antihistamines, opioids, neuroleptics, sleep aids are likely to magnify the effects of clorazepate on the central nervous system. Drugs that may interact with clorazepate include, digoxin, disulfiram, fluoxetine, isoniazid, ketoconazole, levodopa, metoprolol, hormonal contraceptives, probenecid, propranolol, rifampin, theophylline, valproic acid. Selective serotonin reuptake inhibitors (SSRI), cimetidine, macrolide antibiotics and antimycotics inhibit the metabolism of benzodiazepines and may result in increased plasma levels with resultant enhancement of adverse effects. Phenytoin, phenobarbital, and carbamazepine have the opposite effect, with coadministration leading to increased metabolism and decreased therapeutic effects of clorazepate.

Contraindications and Special Caution

Benzodiazepines require special precaution if used in the elderly, children, alcohol- or drug-dependent individuals and individuals with comorbid psychiatric disorders.

Clorazepate if used late in pregnancy, the third trimester, causes a definite risk of severe benzodiazepine withdrawal syndrome in the neonate with symptoms including hypotonia, and reluctance to suck, to apnoeic spells, cyanosis, and impaired metabolic responses to cold stress. Floppy infant syndrome and sedation in the newborn may also occur. Symptoms of floppy infant syndrome and the neonatal benzodiazepine withdrawal syndrome have been reported to persist from hours to months after birth.

Special precaution is required when using clorazepate in the elderly because the elderly metabolise clorazepate more slowly, which may result in excessive drug accumulation. Additionally the elderly are more sensitive to the adverse effects of benzodiazepines compared to younger individuals even when blood plasma levels are the same. Use of benzodiazepines in the elderly is only recommended for 2 weeks and it is also recommended that half of the usual daily dose is prescribed.

Pharmacology

Clorazepate is a “classical” benzodiazepine. Other classical benzodiazepines include chlordiazepoxide, diazepam, clonazepam, oxazepam, lorazepam, nitrazepam, bromazepam and flurazepam. Clorazepate is a long-acting benzodiazepine drug. Clorazepate produces the active metabolite desmethyl-diazepam, which is a partial agonist of the GABAA receptor and has a half life of 20-179 hours; a small amount of desmethyldiazepam is further metabolised into oxazepam. Clorazepate exerts its pharmacological properties via increasing the opening frequency of the chloride ion channel of GABAA receptors. This effect of benzodiazepines requires the presence of the neurotransmitter GABA and results in enhanced inhibitory effects of the neurotransmitter GABA acting on GABAA receptors. Clorazepate, like other benzodiazepines, is widely distributed and is highly bound to plasma proteins; clorazepate also crosses readily over the placenta and into breast milk. Peak plasma levels of the active metabolite desmethyl-diazepam are seen between 30 minutes and 2 hours after oral administration of clorazepate. Clorazepate is completely metabolised to desmethyl-diazepam in the gastrointestinal tract and thus the pharmacological properties of clorazepate are largely due to desmethyldiazepam.

Chemistry

Clorazepate is used in the form of a dipotassium salt. It is unusual among benzodiazepines in that it is freely soluble in water.

Clorazepate can be synthesized starting from 2-amino-5-chlorobenzonitrile, which upon reaction with phenylmagnesium bromide is transformed into 2-amino-5-chlorbenzophenone imine. Reacting this with aminomalonic ester gives a heterocyclisation product, 7-chloro-1,3-dihydro-3-carbethoxy-5-phenyl-2H-benzodiazepin-2-one. Upon hydrolysis using an alcoholic solution of potassium hydroxide forms a dipotassium salt, chlorazepate.

Legal Status

In the United States, clorazepate is listed under Schedule IV of the Controlled Substances Act.

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What is Clonazepam?

Published on by Andrew Marshall2 Comments

Introduction

Clonazepam, sold under the brand name Klonopin among others, is a medication used to prevent and treat seizures, panic disorder, anxiety, and the movement disorder known as akathisia. It is a tranquiliser of the benzodiazepine class. It is typically taken by mouth. Effects begin within one hour and last between six and twelve hours.

Common side effects include sleepiness, poor coordination, and agitation. Long-term use may result in tolerance, dependence, and withdrawal symptoms if stopped abruptly. Dependence occurs in one-third of people who take clonazepam for longer than four weeks. There is an increased risk of suicide, particularly in people who are already depressed. If used during pregnancy it may result in harm to the foetus. Clonazepam binds to GABAA receptors, thus increasing the effect of the chief inhibitory neurotransmitter γ-aminobutyric acid (GABA).

Clonazepam was patented in 1960 and went on sale in 1975 in the United States from Roche. It is available as a generic medication. In 2019, it was the 46th most commonly prescribed medication in the United States, with more than 15 million prescriptions. In many areas of the world it is commonly used as a recreational drug.

Medical Uses

Clonazepam is prescribed for short term management of epilepsy, anxiety, and panic disorder with or without agoraphobia.

Seizures

Clonazepam, like other benzodiazepines, while being a first-line treatment for acute seizures, is not suitable for the long-term treatment of seizures due to the development of tolerance to the anticonvulsant effects.

Clonazepam has been found effective in treating epilepsy in children, and the inhibition of seizure activity seemed to be achieved at low plasma levels of clonazepam. As a result, clonazepam is sometimes used for certain rare childhood epilepsies; however, it has been found to be ineffective in the control of infantile spasms. Clonazepam is mainly prescribed for the acute management of epilepsies. Clonazepam has been found to be effective in the acute control of non-convulsive status epilepticus; however, the benefits tended to be transient in many people, and the addition of phenytoin for lasting control was required in these patients.

It is also approved for treatment of typical and atypical absences (seizures), infantile myoclonic, myoclonic, and akinetic seizures. A subgroup of people with treatment resistant epilepsy may benefit from long-term use of clonazepam; the benzodiazepine clorazepate may be an alternative due to its slow onset of tolerance.

Anxiety Disorders

  • Panic disorder with or without agoraphobia.
  • Clonazepam has also been found effective in treating other anxiety disorders, such as social phobia, but this is an off-label use.

The effectiveness of clonazepam in the short-term treatment of panic disorder has been demonstrated in controlled clinical trials. Some long-term trials have suggested a benefit of clonazepam for up to three years without the development of tolerance but these trials were not placebo-controlled. Clonazepam is also effective in the management of acute mania.

Muscle Disorders

Restless legs syndrome can be treated using clonazepam as a third-line treatment option as the use of clonazepam is still investigational. Bruxism also responds to clonazepam in the short-term. Rapid eye movement sleep behaviour disorder responds well to low doses of clonazepam.

  • The treatment of acute and chronic akathisia induced by neuroleptics, also called antipsychotics.
  • Spasticity related to amyotrophic lateral sclerosis.
  • Alcohol withdrawal syndrome

Other

  • Benzodiazepines, such as clonazepam, are sometimes used for the treatment of mania or acute psychosis-induced aggression. In this context, benzodiazepines are given either alone, or in combination with other first-line drugs such as lithium, haloperidol, or risperidone. The effectiveness of taking benzodiazepines along with antipsychotic medication is unknown, and more research is needed to determine if benzodiazepines are more effective than antipsychotics when urgent sedation is required.
  • Hyperekplexia: A very rare neurologic disorder classically characterised by pronounced startle responses to tactile or acoustic stimuli and hypertonia.
  • Many forms of parasomnia and other sleep disorders are treated with clonazepam..
  • It is not effective for preventing migraines.

Contraindications

  • Coma.
  • Current alcohol use disorder.
  • Current substance use disorder.
  • Respiratory depression.

Adverse Effects

In September 2020, the US Food and Drug Administration (FDA) required the boxed warning be updated for all benzodiazepine medicines to describe the risks of abuse, misuse, addiction, physical dependence, and withdrawal reactions consistently across all the medicines in the class.

Common

  • Sedation.
  • Motor impairment.

Less Common

  • Confusion.
  • Irritability and aggression.
  • Psychomotor agitation.
  • Lack of motivation.
  • Loss of libido.
  • Impaired motor function.
  • Impaired coordination.
  • Impaired balance.
  • Dizziness.
  • Cognitive impairments.
  • Hallucinations.
  • Short-term memory loss.
  • Anterograde amnesia (common with higher doses).
  • Some users report hangover-like symptoms of drowsiness, headaches, sluggishness, and irritability upon waking up if the medication was taken before sleep.
    • This is likely the result of the medication’s long half-life, which continues to affect the user after waking up.
    • While benzodiazepines induce sleep, they tend to reduce the quality of sleep by suppressing or disrupting REM sleep.
    • After regular use, rebound insomnia may occur when discontinuing clonazepam.
  • Benzodiazepines may cause or worsen depression.

Occasional

  • Dysphoria.
  • Induction of seizures or increased frequency of seizures.
  • Personality changes.
  • Behavioural disturbances.
  • Ataxia.

Rare

  • Cognitive Euphoria.
  • Suicide through disinhibition.
  • Psychosis.
  • Incontinence.
  • Liver damage.
  • Paradoxical behavioural disinhibition (most frequently in children, the elderly, and in persons with developmental disabilities).
  • Rage.
  • Excitement.
  • Impulsivity.
  • The long-term effects of clonazepam can include depression, disinhibition, and sexual dysfunction.

Drowsiness

Clonazepam, like other benzodiazepines, may impair a person’s ability to drive or operate machinery. The central nervous system depressing effects of the drug can be intensified by alcohol consumption, and therefore alcohol should be avoided while taking this medication. Benzodiazepines have been shown to cause dependence. Patients dependent on clonazepam should be slowly titrated off under the supervision of a qualified healthcare professional to reduce the intensity of withdrawal or rebound symptoms.

Withdrawal-Related

  • Anxiety.
  • Irritability.
  • Insomnia.
  • Tremors.
  • Headaches.
  • Stomach pain.
  • Hallucinations.
  • Suicidal thoughts or urges.
  • Depression.
  • Fatigue.
  • Dizziness.
  • Sweating.
  • Confusion.
  • Potential to exacerbate existing panic disorder upon discontinuation.
  • Seizures similar to delirium tremens (with long-term use of excessive doses).

Benzodiazepines such as clonazepam can be very effective in controlling status epilepticus, but, when used for longer periods of time, some potentially serious side-effects may develop, such as interference with cognitive functions and behaviour. Many individuals treated on a long-term basis develop a dependence. Physiological dependence was demonstrated by flumazenil-precipitated withdrawal. Use of alcohol or other central nervous system (CNS)-depressants while taking clonazepam greatly intensifies the effects (and side effects) of the drug.

A recurrence of symptoms of the underlying disease should be separated from withdrawal symptoms.

Tolerance and Withdrawal

Refer to Benzodiazepine Withdrawal Syndrome.

Like all benzodiazepines, clonazepam is a GABA-positive allosteric modulator. One-third of individuals treated with benzodiazepines for longer than four weeks develop a dependence on the drug and experience a withdrawal syndrome upon dose reduction. High dosage and long-term use increase the risk and severity of dependence and withdrawal symptoms. Withdrawal seizures and psychosis can occur in severe cases of withdrawal, and anxiety and insomnia can occur in less severe cases of withdrawal. A gradual reduction in dosage reduces the severity of the benzodiazepine withdrawal syndrome. Due to the risks of tolerance and withdrawal seizures, clonazepam is generally not recommended for the long-term management of epilepsies. Increasing the dose can overcome the effects of tolerance, but tolerance to the higher dose may occur and adverse effects may intensify. The mechanism of tolerance includes receptor desensitisation, down regulation, receptor decoupling, and alterations in subunit composition and in gene transcription coding.

Tolerance to the anticonvulsant effects of clonazepam occurs in both animals and humans. In humans, tolerance to the anticonvulsant effects of clonazepam occurs frequently. Chronic use of benzodiazepines can lead to the development of tolerance with a decrease of benzodiazepine binding sites. The degree of tolerance is more pronounced with clonazepam than with chlordiazepoxide. In general, short-term therapy is more effective than long-term therapy with clonazepam for the treatment of epilepsy. Many studies have found that tolerance develops to the anticonvulsant properties of clonazepam with chronic use, which limits its long-term effectiveness as an anticonvulsant.

Abrupt or over-rapid withdrawal from clonazepam may result in the development of the benzodiazepine withdrawal syndrome, causing psychosis characterised by dysphoric manifestations, irritability, aggressiveness, anxiety, and hallucinations. Sudden withdrawal may also induce the potentially life-threatening condition, status epilepticus. Anti-epileptic drugs, benzodiazepines such as clonazepam in particular, should be reduced in dose slowly and gradually when discontinuing the drug to mitigate withdrawal effects. Carbamazepine has been tested in the treatment of clonazepam withdrawal but was found to be ineffective in preventing clonazepam withdrawal-induced status epilepticus from occurring.

Overdose

Refer to Benzodiazepine Overdose.

Excess doses may result in:

  • Difficulty staying awake.
  • Mental confusion.
  • Impaired motor functions.
  • Impaired reflexes.
  • Impaired coordination.
  • Impaired balance.
  • Dizziness.
  • Respiratory depression.
  • Low blood pressure.
  • Coma.

Coma can be cyclic, with the individual alternating from a comatose state to a hyper-alert state of consciousness, which occurred in a four-year-old boy who overdosed on clonazepam. The combination of clonazepam and certain barbiturates (for example, amobarbital), at prescribed doses has resulted in a synergistic potentiation of the effects of each drug, leading to serious respiratory depression.

Overdose symptoms may include extreme drowsiness, confusion, muscle weakness, and fainting.

Detection in Biological Fluids

Clonazepam and 7-aminoclonazepam may be quantified in plasma, serum, or whole blood in order to monitor compliance in those receiving the drug therapeutically. Results from such tests can be used to confirm the diagnosis in potential poisoning victims or to assist in the forensic investigation in a case of fatal overdosage. Both the parent drug and 7-aminoclonazepam are unstable in biofluids, and therefore specimens should be preserved with sodium fluoride, stored at the lowest possible temperature and analysed quickly to minimise losses.

Special Precautions

The elderly metabolise benzodiazepines more slowly than younger people and are also more sensitive to the effects of benzodiazepines, even at similar blood plasma levels. Doses for the elderly are recommended to be about half of that given to younger adults and are to be administered for no longer than two weeks. Long-acting benzodiazepines such as clonazepam are not generally recommended for the elderly due to the risk of drug accumulation.

The elderly are especially susceptible to increased risk of harm from motor impairments and drug accumulation side effects. Benzodiazepines also require special precaution if used by individuals that may be pregnant, alcohol- or drug-dependent, or may have comorbid psychiatric disorders. Clonazepam is generally not recommended for use in elderly people for insomnia due to its high potency relative to other benzodiazepines.

Clonazepam is not recommended for use in those under 18. Use in very young children may be especially hazardous. Of anticonvulsant drugs, behavioural disturbances occur most frequently with clonazepam and phenobarbital.

Doses higher than 0.5-1 mg per day are associated with significant sedation.

Clonazepam may aggravate hepatic porphyria.

Clonazepam is not recommended for patients with chronic schizophrenia. A 1982 double-blinded, placebo-controlled study found clonazepam increases violent behaviour in individuals with chronic schizophrenia.

Clonazepam has similar effectiveness to other benzodiazepines at often a lower dose.

Interactions

Clonazepam decreases the levels of carbamazepine, and, likewise, clonazepam’s level is reduced by carbamazepine. Azole antifungals, such as ketoconazole, may inhibit the metabolism of clonazepam. Clonazepam may affect levels of phenytoin (diphenylhydantoin). In turn, Phenytoin may lower clonazepam plasma levels by increasing the speed of clonazepam clearance by approximately 50% and decreasing its half-life by 31%. Clonazepam increases the levels of primidone and phenobarbital.

Combined use of clonazepam with certain antidepressants, anticonvulsants (such as phenobarbital, phenytoin, and carbamazepine), sedative antihistamines, opiates, and antipsychotics, nonbenzodiazepines (such as zolpidem), and alcohol may result in enhanced sedative effects.

Pregnancy

There is some medical evidence of various malformations (for example, cardiac or facial deformations when used in early pregnancy); however, the data is not conclusive. The data are also inconclusive on whether benzodiazepines such as clonazepam cause developmental deficits or decreases in IQ in the developing foetus when taken by the mother during pregnancy. Clonazepam, when used late in pregnancy, may result in the development of a severe benzodiazepine withdrawal syndrome in the neonate. Withdrawal symptoms from benzodiazepines in the neonate may include hypotonia, apnoeic spells, cyanosis, and impaired metabolic responses to cold stress.

The safety profile of clonazepam during pregnancy is less clear than that of other benzodiazepines, and if benzodiazepines are indicated during pregnancy, chlordiazepoxide and diazepam may be a safer choice. The use of clonazepam during pregnancy should only occur if the clinical benefits are believed to outweigh the clinical risks to the foetus. Caution is also required if clonazepam is used during breastfeeding. Possible adverse effects of use of benzodiazepines such as clonazepam during pregnancy include: miscarriage, malformation, intrauterine growth retardation, functional deficits, carcinogenesis, and mutagenesis. Neonatal withdrawal syndrome associated with benzodiazepines include hypertonia, hyperreflexia, restlessness, irritability, abnormal sleep patterns, inconsolable crying, tremors, or jerking of the extremities, bradycardia, cyanosis, suckling difficulties, apnoea, risk of aspiration of feeds, diarrhoea and vomiting, and growth retardation. This syndrome can develop between three days to three weeks after birth and can have a duration of up to several months. The pathway by which clonazepam is metabolised is usually impaired in newborns. If clonazepam is used during pregnancy or breastfeeding, it is recommended that serum levels of clonazepam are monitored and that signs of central nervous system depression and apnoea are also checked for. In many cases, non-pharmacological treatments, such as relaxation therapy, psychotherapy, and avoidance of caffeine, can be an effective and safer alternative to the use of benzodiazepines for anxiety in pregnant women.

Pharmacology

Mechanism of Action

Clonazepam enhances the activity of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) in the central nervous system to give its anticonvulsant, skeletal muscle relaxant, and anxiolytic effects. It acts by binding to the benzodiazepine site of the GABA receptors, which enhances the electric effect of GABA binding on neurons, resulting in an increased influx of chloride ions into the neurons. This further results in an inhibition of synaptic transmission across the central nervous system.

Benzodiazepines do not have any effect on the levels of GABA in the brain. Clonazepam has no effect on GABA levels and has no effect on gamma-aminobutyric acid transaminase. Clonazepam does, however, affect glutamate decarboxylase activity. It differs from other anticonvulsant drugs it was compared to in a study.

Clonazepam’s primary mechanism of action is the modulation of GABA function in the brain, by the benzodiazepine receptor, located on GABAA receptors, which, in turn, leads to enhanced GABAergic inhibition of neuronal firing. Benzodiazepines do not replace GABA, but instead enhance the effect of GABA at the GABAA receptor by increasing the opening frequency of chloride ion channels, which leads to an increase in GABA’s inhibitory effects and resultant central nervous system depression. In addition, clonazepam decreases the utilisation of 5-HT (serotonin) by neurons and has been shown to bind tightly to central-type benzodiazepine receptors. Because clonazepam is effective in low milligram doses (0.5 mg clonazepam = 10 mg diazepam), it is said to be among the class of “highly potent” benzodiazepines. The anticonvulsant properties of benzodiazepines are due to the enhancement of synaptic GABA responses, and the inhibition of sustained, high-frequency repetitive firing.

Benzodiazepines, including clonazepam, bind to mouse glial cell membranes with high affinity. Clonazepam decreases release of acetylcholine in the feline brain and decreases prolactin release in rats. Benzodiazepines inhibit cold-induced thyroid-stimulating hormone (also known as TSH or thyrotropin) release. Benzodiazepines act via micromolar benzodiazepine binding sites as Ca2+ channel blockers and significantly inhibit depolarisation-sensitive calcium uptake in experimentation on rat brain cell components. This has been conjectured as a mechanism for high-dose effects on seizures in the study.

Clonazepam is a 2′-chlorinated derivative of nitrazepam, which increases its potency due to electron-attracting effect of the halogen in the ortho-position.

Pharmacokinetics

Clonazepam is lipid-soluble, rapidly crosses the blood-brain barrier, and penetrates the placenta. It is extensively metabolised into pharmacologically inactive metabolites, with only 2% of the unchanged drug excreted in the urine. Clonazepam is metabolised extensively via nitroreduction by cytochrome P450 enzymes, including CYP3A4. Erythromycin, clarithromycin, ritonavir, itraconazole, ketoconazole, nefazodone, cimetidine, and grapefruit juice are inhibitors of CYP3A4 and can affect the metabolism of benzodiazepines. It has an elimination half-life of 19-60 hours. Peak blood concentrations of 6.5-13.5 ng/mL were usually reached within 1-2 hours following a single 2 mg oral dose of micronized clonazepam in healthy adults. In some individuals, however, peak blood concentrations were reached at 4-8 hours.

Clonazepam passes rapidly into the central nervous system, with levels in the brain corresponding with levels of unbound clonazepam in the blood serum. Clonazepam plasma levels are very unreliable amongst patients. Plasma levels of clonazepam can vary as much as tenfold between different patients.

Clonazepam has plasma protein binding of 85%. Clonazepam passes through the blood-brain barrier easily, with blood and brain levels corresponding equally with each other. The metabolites of clonazepam include 7-aminoclonazepam, 7-acetaminoclonazepam and 3-hydroxy clonazepam. These metabolites are excreted by the kidney.

It is effective for 6-8 hours in children, and 6-12 in adults.

Society and Culture

Recreational Use

Refer to Benzodiazepine Misuse.

A 2006 US government study of hospital emergency department (ED) visits found that sedative-hypnotics were the most frequently implicated pharmaceutical drug in visits, with benzodiazepines accounting for the majority of these. Clonazepam was the second most frequently implicated benzodiazepine in ED visits. Alcohol alone was responsible for over twice as many ED visits as clonazepam in the same study. The study examined the number of times the non-medical use of certain drugs was implicated in an ED visit. The criteria for non-medical use in this study were purposefully broad, and include, for example, drug abuse, accidental or intentional overdose, or adverse reactions resulting from legitimate use of the medication.

Formulations

Clonazepam was approved in the United States as a generic drug in 1997 and is now manufactured and marketed by several companies.

Clonazepam is available as tablets and orally disintegrating tablets (wafers) an oral solution (drops), and as a solution for injection or intravenous infusion.

Brand Names

It is marketed under the trade name Rivotril by Roche in Argentina, Australia, Austria, Bangladesh, Belgium, Brazil, Bulgaria, Canada, Colombia, Costa Rica, Croatia, the Czech Republic, Denmark, Estonia,[136] Germany, Hungary, Iceland, Ireland, Italy, China, Mexico, the Netherlands, Norway, Portugal, Peru, Pakistan, Romania, Serbia, South Africa, South Korea, Spain, Turkey, and the United States; Emcloz, Linotril and Clonotril in India and other parts of Europe; under the name Riklona in Indonesia and Malaysia; and under the trade name Klonopin by Roche in the United States. Other names, such as Clonoten, Ravotril, Rivotril, Iktorivil, Clonex (Israel), Paxam, Petril, Naze, Zilepam and Kriadex, are known throughout the world.

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What is Bromazolam?

Published on by Andrew MarshallLeave a comment

Introduction

Bromazolam (XLI-268) is a triazolobenzodiazepine (TBZD) which was first synthesised in 1976, but was never marketed. It has subsequently been sold as a designer drug, first being definitively identified by the EMCDDA in Sweden in 2016.

Outline

It is the bromo instead of chloro analogue of alprazolam and has similar sedative and anxiolytic effects to it and other benzodiazepines. Bromazolam is a non subtype selective agonist at the benzodiazepine site of GABAA receptors, with a binding affinity of 2.81nM at the α1 subtype, 0.69nM at α2 and 0.62nM at α5.

This page is based on the copyrighted Wikipedia article < https://en.wikipedia.org/wiki/Bromazolam >; it is used under the Creative Commons Attribution-ShareAlike 3.0 Unported License (CC-BY-SA). You may redistribute it, verbatim or modified, providing that you comply with the terms of the CC-BY-SA.