Clorazepate

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Tablet, Oral, as dipotassium:

Tranxene-T: 3.75 mg [DSC] [contains fd&c blue #2 (indigotine)]

Tranxene-T: 7.5 mg [contains fd&c yellow #6 (sunset yellow)]

Tranxene-T: 7.5 mg [DSC] [scored; contains fd&c yellow #6 (sunset yellow)]

Generic: 3.75 mg, 7.5 mg, 15 mg

Pharmacology

Mechanism of Action

Binds to stereospecific benzodiazepine receptors on the postsynaptic GABA neuron at several sites within the central nervous system, including the limbic system and reticular formation. Enhancement of the inhibitory effect of GABA on neuronal excitability results by increased neuronal membrane permeability to chloride ions. This shift in chloride ions results in hyperpolarization (a less excitable state) and stabilization. Benzodiazepine receptors and effects appear to be linked to the GABA-A receptors. Benzodiazepines do not bind to GABA-B receptors (Nelson 1999).

Pharmacokinetics/Pharmacodynamics

Distribution

Nordiazepam: V_d: 0.7 to 2.2 L/kg (Riss, 2008)

Metabolism

Rapidly decarboxylated to nordiazepam (active) in acidic stomach prior to absorption; nordiazepam is hepatically hydroxylated by CYP 2C19 and CYP3A4 to oxazepam (active) and undergoes glucuronidation to form a glucuronide conjugate (Riss, 2008)

Excretion

Urine (62% to 67%; primarily metabolites of conjugated oxazepam); feces (15% to 19%)

Time to Peak

Serum: ~0.5 to 2 hour (Carrigan, 1977; Riss, 2008)

Half-Life Elimination

Nordiazepam: 20 to 160 hours; Oxazepam: 6 to 24 hours (Riss, 2008)

Protein Binding

Nordiazepam: 97% to 98%

Use: Labeled Indications

Alcohol withdrawal: Symptomatic relief of acute alcohol withdrawal.

Anxiety disorders: Management of anxiety disorders and short-term relief of the symptoms of anxiety.

Partial seizures: Adjunct therapy in the management of partial seizures.

Contraindications

Hypersensitivity to clorazepate or any component of the formulation; acute narrow-angle glaucoma

Documentation of allergenic cross-reactivity for benzodiazepines is limited. However, because of similarities in chemical structure and/or pharmacologic actions, the possibility of cross-sensitivity cannot be ruled out with certainty.

Canadian labeling: Additional contraindications (not in US labeling): Myasthenia gravis.

Dosage and Administration

Dosing: Adult

Anxiety disorders: Oral: Usual dosage: 30 mg/day in divided doses (range: 15 to 60 mg/day) or 15 mg at bedtime; adjust dose based on patient response. Note: For debilitated patients, initiate at 7.5 to 15 mg/day

Alcohol withdrawal: Oral: Maximum dose: 90 mg/day.

Day 1: 30 mg initially, followed by 30 to 60 mg in divided doses.

Day 2: 45 to 90 mg in divided doses.

Day 3: 22.5 to 45 mg in divided doses.

Day 4: 15 to 30 mg in divided doses.

Beyond day 4: Gradually reduce the daily dose to 7.5 to 15 mg.

Partial seizures (adjunctive therapy): Oral: Initial: Up to 7.5 mg 3 times daily; increase in ≤7.5 mg increments at weekly intervals; maximum dose: 90 mg/day.

Dosing: Geriatric

If use is necessary, start with low doses and titrate slowly to effect.

Anxiety disorders: Oral: Initial: 7.5 to 15 mg/day

Other indications: Refer to adult dosing.

Dosing: Pediatric

Anxiety disorders: Limited data available (Kliegman 2007):

Children 9 to 12 years: Oral: Initial: 3.75 mg twice daily; titrate weekly as needed; maximum daily dose: 60 mg/day

Adolescents: Oral: Initial: 7.5 mg 2 to 3 times daily; titrate weekly as needed; maximum daily dose: 90 mg/day

Seizures:

Children <9 years: Limited data available: Oral: Initial: 0.3 to 0.75 mg/kg/day in 1 to 3 divided doses or 3.75 mg once to three times daily; maximum initial daily dose: 1 mg/kg/day. Titrate weekly as needed; maximum daily dose: 3 mg/kg/day or 60 mg/day, whichever is less. In trials, subjects observed as having an excellent response reported a mean dose range of 0.79 to 1.33 mg/kg/day (Fujii 1987; Mimaki 1984; Naidu 1986; Sugai 2004)

Children 9 to 12 years: Oral: Initial: Up to 7.5 mg twice daily; increase in ≤7.5 mg increments at weekly intervals, maximum daily dose: 60 mg/day

Adolescents: Oral: Initial: Up to 7.5 mg 3 times daily; increase in ≤7.5 mg increments at weekly intervals; usual dose range: 0.5 to 1 mg/kg/day; maximum daily dose: 90 mg/day

Administration

May administer with food or water to decrease GI upset.

Storage

Store at 20°C to 25°C (68°F to 77°F). Protect from moisture.

Drug Interactions

Alcohol (Ethyl): CNS Depressants may enhance the CNS depressant effect of Alcohol (Ethyl). Monitor therapy

Alizapride: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Azelastine (Nasal): CNS Depressants may enhance the CNS depressant effect of Azelastine (Nasal). Avoid combination

Blonanserin: CNS Depressants may enhance the CNS depressant effect of Blonanserin. Consider therapy modification

Bosentan: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Brexanolone: CNS Depressants may enhance the CNS depressant effect of Brexanolone. Monitor therapy

Brimonidine (Topical): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Bromopride: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Bromperidol: May enhance the CNS depressant effect of CNS Depressants. Avoid combination

Buprenorphine: CNS Depressants may enhance the CNS depressant effect of Buprenorphine. Management: Consider reduced doses of other CNS depressants, and avoiding such drugs in patients at high risk of buprenorphine overuse/self-injection. Initiate buprenorphine at lower doses in patients already receiving CNS depressants. Consider therapy modification

Cannabidiol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Cannabis: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Chlormethiazole: May enhance the CNS depressant effect of CNS Depressants. Management: Monitor closely for evidence of excessive CNS depression. The chlormethiazole labeling states that an appropriately reduced dose should be used if such a combination must be used. Consider therapy modification

Chlorphenesin Carbamate: May enhance the adverse/toxic effect of CNS Depressants. Monitor therapy

CloZAPine: Benzodiazepines may enhance the adverse/toxic effect of CloZAPine. Management: Consider decreasing the dose of (or possibly discontinuing) benzodiazepines prior to initiating clozapine. Consider therapy modification

CNS Depressants: May enhance the adverse/toxic effect of other CNS Depressants. Monitor therapy

CYP3A4 Inducers (Moderate): May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

CYP3A4 Inducers (Strong): May increase the metabolism of CYP3A4 Substrates (High risk with Inducers). Management: Consider an alternative for one of the interacting drugs. Some combinations may be specifically contraindicated. Consult appropriate manufacturer labeling. Consider therapy modification

Dabrafenib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Seek alternatives to the CYP3A4 substrate when possible. If concomitant therapy cannot be avoided, monitor clinical effects of the substrate closely (particularly therapeutic effects). Consider therapy modification

Deferasirox: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Dimethindene (Topical): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Doxylamine: May enhance the CNS depressant effect of CNS Depressants. Management: The manufacturer of Diclegis (doxylamine/pyridoxine), intended for use in pregnancy, specifically states that use with other CNS depressants is not recommended. Monitor therapy

Dronabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Droperidol: May enhance the CNS depressant effect of CNS Depressants. Management: Consider dose reductions of droperidol or of other CNS agents (eg, opioids, barbiturates) with concomitant use. Exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Consider therapy modification

Enzalutamide: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Concurrent use of enzalutamide with CYP3A4 substrates that have a narrow therapeutic index should be avoided. Use of enzalutamide and any other CYP3A4 substrate should be performed with caution and close monitoring. Consider therapy modification

Erdafitinib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Esketamine: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Flunitrazepam: CNS Depressants may enhance the CNS depressant effect of Flunitrazepam. Consider therapy modification

Fosamprenavir: May increase the serum concentration of Clorazepate. Monitor therapy

HYDROcodone: CNS Depressants may enhance the CNS depressant effect of HYDROcodone. Management: Avoid concomitant use of hydrocodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

HydrOXYzine: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Ivosidenib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Kava Kava: May enhance the adverse/toxic effect of CNS Depressants. Monitor therapy

Lemborexant: May enhance the CNS depressant effect of CNS Depressants. Management: Dosage adjustments of lemborexant and of concomitant CNS depressants may be necessary when administered together because of potentially additive CNS depressant effects. Close monitoring for CNS depressant effects is necessary. Consider therapy modification

Lofexidine: May enhance the CNS depressant effect of CNS Depressants. Management: Drugs listed as exceptions to this monograph are discussed in further detail in separate drug interaction monographs. Monitor therapy

Lorlatinib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Avoid concurrent use of lorlatinib with any CYP3A4 substrates for which a minimal decrease in serum concentrations of the CYP3A4 substrate could lead to therapeutic failure and serious clinical consequences. Consider therapy modification

Magnesium Sulfate: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Melatonin: May enhance the sedative effect of Benzodiazepines. Monitor therapy

Methadone: Benzodiazepines may enhance the CNS depressant effect of Methadone. Management: Clinicians should generally avoid concurrent use of methadone and benzodiazepines when possible; any combined use should be undertaken with extra caution. Consider therapy modification

Methotrimeprazine: CNS Depressants may enhance the CNS depressant effect of Methotrimeprazine. Methotrimeprazine may enhance the CNS depressant effect of CNS Depressants. Management: Reduce adult dose of CNS depressant agents by 50% with initiation of concomitant methotrimeprazine therapy. Further CNS depressant dosage adjustments should be initiated only after clinically effective methotrimeprazine dose is established. Consider therapy modification

MetyroSINE: CNS Depressants may enhance the sedative effect of MetyroSINE. Monitor therapy

Minocycline (Systemic): May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Mitotane: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Doses of CYP3A4 substrates may need to be adjusted substantially when used in patients being treated with mitotane. Consider therapy modification

Nabilone: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

OLANZapine: May enhance the adverse/toxic effect of Benzodiazepines. Management: Avoid concomitant use of parenteral benzodiazepines and IM olanzapine due to risks of additive adverse events (e.g., cardiorespiratory depression). Olanzapine prescribing information provides no specific recommendations regarding oral administration. Avoid combination

Opioid Agonists: CNS Depressants may enhance the CNS depressant effect of Opioid Agonists. Management: Avoid concomitant use of opioid agonists and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Orphenadrine: CNS Depressants may enhance the CNS depressant effect of Orphenadrine. Avoid combination

Oxomemazine: May enhance the CNS depressant effect of CNS Depressants. Avoid combination

OxyCODONE: CNS Depressants may enhance the CNS depressant effect of OxyCODONE. Management: Avoid concomitant use of oxycodone and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Paraldehyde: CNS Depressants may enhance the CNS depressant effect of Paraldehyde. Avoid combination

Perampanel: May enhance the CNS depressant effect of CNS Depressants. Management: Patients taking perampanel with any other drug that has CNS depressant activities should avoid complex and high-risk activities, particularly those such as driving that require alertness and coordination, until they have experience using the combination. Consider therapy modification

Piribedil: CNS Depressants may enhance the CNS depressant effect of Piribedil. Monitor therapy

Pramipexole: CNS Depressants may enhance the sedative effect of Pramipexole. Monitor therapy

Ritonavir: May increase the serum concentration of Clorazepate. Monitor therapy

ROPINIRole: CNS Depressants may enhance the sedative effect of ROPINIRole. Monitor therapy

Rotigotine: CNS Depressants may enhance the sedative effect of Rotigotine. Monitor therapy

Rufinamide: May enhance the adverse/toxic effect of CNS Depressants. Specifically, sleepiness and dizziness may be enhanced. Monitor therapy

Saquinavir: May increase the serum concentration of Clorazepate. Monitor therapy

Sarilumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Selective Serotonin Reuptake Inhibitors: CNS Depressants may enhance the adverse/toxic effect of Selective Serotonin Reuptake Inhibitors. Specifically, the risk of psychomotor impairment may be enhanced. Monitor therapy

Siltuximab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Sodium Oxybate: Benzodiazepines may enhance the CNS depressant effect of Sodium Oxybate. Avoid combination

Suvorexant: CNS Depressants may enhance the CNS depressant effect of Suvorexant. Management: Dose reduction of suvorexant and/or any other CNS depressant may be necessary. Use of suvorexant with alcohol is not recommended, and the use of suvorexant with any other drug to treat insomnia is not recommended. Consider therapy modification

Tapentadol: May enhance the CNS depressant effect of CNS Depressants. Management: Avoid concomitant use of tapentadol and benzodiazepines or other CNS depressants when possible. These agents should only be combined if alternative treatment options are inadequate. If combined, limit the dosages and duration of each drug. Consider therapy modification

Teduglutide: May increase the serum concentration of Benzodiazepines. Monitor therapy

Tetrahydrocannabinol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Tetrahydrocannabinol and Cannabidiol: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Thalidomide: CNS Depressants may enhance the CNS depressant effect of Thalidomide. Avoid combination

Theophylline Derivatives: May diminish the therapeutic effect of Benzodiazepines. Consider therapy modification

Tobacco (Smoked): May decrease serum concentrations of the active metabolite(s) of Clorazepate. Monitor therapy

Tocilizumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Trimeprazine: May enhance the CNS depressant effect of CNS Depressants. Monitor therapy

Yohimbine: May diminish the therapeutic effect of Antianxiety Agents. Monitor therapy

Zolpidem: CNS Depressants may enhance the CNS depressant effect of Zolpidem. Management: Reduce the Intermezzo brand sublingual zolpidem adult dose to 1.75 mg for men who are also receiving other CNS depressants. No such dose change is recommended for women. Avoid use with other CNS depressants at bedtime; avoid use with alcohol. Consider therapy modification

Test Interactions

Decreased hematocrit; abnormal liver and renal function tests

Adverse Reactions

Frequency not defined.

Cardiovascular: Hypotension

Central nervous system: Anxiety, ataxia, confusion, depression, dizziness, drowsiness, dysarthria, fatigue, headache, insomnia, irritability, memory impairment, nervousness, slurred speech

Dermatologic: Skin rash

Endocrine & metabolic: Decreased libido

Gastrointestinal: Constipation, decreased appetite, diarrhea, increased appetite, nausea, vomiting, xerostomia

Hepatic: Increased serum transaminases, jaundice

Neuromuscular & skeletal: Tremor

Ophthalmic: Blurred vision, diplopia

Warnings/Precautions

Concerns related to adverse effects:

• Anterograde amnesia: Benzodiazepines have been associated with anterograde amnesia (Nelson 1999).
• CNS depression: May cause CNS depression, which may impair physical or mental abilities; patients must be cautioned about performing tasks which require mental alertness (eg, operating machinery or driving).
• Paradoxical reactions: Paradoxical reactions, including hyperactive or aggressive behavior, have been reported with benzodiazepines; risk may be increased in adolescent/pediatric patients, geriatric patients, or patients with a history of alcohol use disorder or psychiatric/personality disorders (Mancuso 2004).
• Sleep-related activities: Hazardous sleep-related activities such as sleep-driving, cooking and eating food, and making phone calls while asleep have been noted with benzodiazepines (Dolder 2008).
• Suicidal ideation: Pooled analysis of trials involving various antiepileptics (regardless of indication) showed an increased risk of suicidal thoughts/behavior (incidence rate: 0.43% treated patients compared to 0.24% of patients receiving placebo); risk observed as early as 1 week after initiation and continued through duration of trials (most trials ≤24 weeks). Monitor all patients for notable changes in behavior that might indicate suicidal thoughts or depression; notify healthcare provider immediately if symptoms occur.

Disease-related concerns:

• Depression: Use caution in patients with depression, particularly if suicidal risk may be present. Not recommended for use in depressive neuroses.
• Drug abuse: Use with caution in patients with a history of drug abuse or acute alcoholism; potential for drug dependency exists. Tolerance and psychological and physical dependence may occur with prolonged use.
• Hepatic impairment: Use with caution in patients with hepatic impairment.
• Renal impairment: Use with caution in patients with renal impairment.
• Respiratory disease: Use with caution in patients with respiratory disease. Benzodiazepines may cause significant respiratory depression.

Concurrent drug therapy issues:

• Concomitant use with opioids: [US Boxed warning]: Concomitant use of benzodiazepines and opioids may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant prescribing of these drugs for use in patients for whom alternative treatment options are inadequate. Limit dosages and durations to the minimum required. Follow patients for signs and symptoms of respiratory depression and sedation.
• Drug-drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information.

Special populations:

• Debilitated patients: Use with caution in debilitated patients; dosage adjustment recommended.
• Elderly: Avoid or use with extreme caution in the elderly. Elderly patients may be at an increased risk of death with use; risk has been found highest within the first 4 months of use in elderly dementia patients (Jennum 2015; Saarelainen 2018).
• Fall risk: Use with extreme caution in patients who are at risk of falls; benzodiazepines have been associated with falls and traumatic injury (Nelson 1999).

Other warnings/precautions:

• Appropriate use: Does not have analgesic, antidepressant, or antipsychotic properties. Not recommended for use in psychotic reactions.
• Tolerance: Clorazepate is a long half-life benzodiazepine. Duration of action after a single dose is determined by redistribution rather than metabolism. Tolerance develops to the anticonvulsant effects. It does not develop to the anxiolytic effects (Vinkers 2012). Chronic use of this agent may increase the perioperative benzodiazepine dose needed to achieve desired effect.
• Withdrawal: Rebound or withdrawal symptoms may occur following abrupt discontinuation or large decreases in dose. Use caution when reducing dose or withdrawing therapy; decrease slowly and monitor for withdrawal symptoms. Flumazenil may cause withdrawal in patients receiving long-term benzodiazepine therapy.

Monitoring Parameters

Excessive CNS depression, respiratory rate, and cardiovascular status; with prolonged use: CBC, liver enzymes, renal function; signs and symptoms of suicidality (eg, anxiety, depression, behavior changes).

Pregnancy

Pregnancy Considerations

Nordiazepam, the active metabolite of clorazepate, crosses the placenta and is measurable in cord blood and amniotic fluid. Teratogenic effects have been observed with some benzodiazepines (including clorazepate); however, additional studies are needed. The incidence of premature birth and low birth weights may be increased following maternal use of benzodiazepines; hypoglycemia and respiratory problems in the neonate may occur following exposure late in pregnancy. Neonatal withdrawal symptoms may occur within days to weeks after birth and “floppy infant syndrome” (which also includes withdrawal symptoms) has been reported with some benzodiazepines (Bergman 1992; Iqbal 2002; Patel 1980; Rey 1979; Wikner 2007). A combination of factors influences the potential teratogenicity of anticonvulsant therapy. When treating women with epilepsy, monotherapy with the lowest effective dose and avoidance of medications known to have a high incidence of teratogenic effects is recommended (Harden 2009; Wlodarczyk 2012).

Patients exposed to clorazepate during pregnancy are encouraged to enroll themselves into the AED Pregnancy Registry by calling 1-888-233-2334. Additional information is available at www.aedpregnancyregistry.org.

Patient Education

What is this drug used for?

• It is used to treat alcohol withdrawal.
• It is used to treat anxiety.
• It is used to treat seizures.
• It may be given to you for other reasons. Talk with the doctor.

Frequently reported side effects of this drug

• Fatigue
• Headache
• Nausea
• Dry mouth

Other side effects of this drug: Talk with your doctor right away if you have any of these signs of:

• Vision changes
• Change in balance
• Confusion
• Severe loss of strength and energy
• Seizures
• Unable to pass urine
• Change in amount of urine passed
• Slurred speech
• Tremors
• Trouble sleeping
• Severe dizziness
• Passing out
• Depression like thoughts of suicide, anxiety, emotional instability, or confusion.
• Agitation
• Irritability
• Panic attacks
• Mood changes
• Signs of a significant reaction like wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from the healthcare provider. You must talk with the healthcare provider for complete information about the risks and benefits of using this medicine.