HIGHLIGHTS OF PRESCRIBING INFORMATION
These highlights do not include all the information needed to use HALCION safely and effectively. See full prescribing information for HALCION.
HALCION® (triazolam) tablets, for oral use, CIV
Initial U.S. Approval: 1982
WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS
If you provide additional keywords, you may be able to browse through our database of Scientific Response Documents.
HALCION®, CIV (triazolam)
If you provide additional keywords, you may be able to browse through our database of Scientific Response Documents.
HALCION®, CIV Quick Finder
WARNING: RISKS FROM CONCOMITANT USE WITH OPIOIDS
- 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.
2 DOSAGE AND ADMINISTRATION
2.1 Dosing Information
The recommended dosage is 0.25 mg once daily before bedtime. A dosage of 0.125 mg once daily may be sufficient for some patients (e.g., patients with low body weight). A dosage of 0.5 mg should be used only for patients who do not respond adequately to a trial of a lower dose. The maximum recommended dosage is 0.5 mg once daily.
Use the lowest effective dose for the patient as there are significant dose related adverse reactions.
Prescriptions for Halcion should be written for short-term use (7 to 10 days) and it should not be prescribed in quantities exceeding a 1-month supply.
2.2 Use in Geriatric Patients
In geriatric patients, the recommended dosage is 0.125 mg to 0.25 mg once daily. Initiate therapy at 0.125 mg once daily. The 0.25 mg dose should be used only for patients who do not respond to a trial of the lower dose. The maximum recommended dosage is 0.25 mg once daily. Elderly patients have an increased risk of dose related adverse reactions [see Use in Specific Populations (8.5)].
Halcion is contraindicated in:
- Patients with known hypersensitivity to triazolam, any of component of Halcion, or other benzodiazepines. Reactions consistent with angioedema (involving the tongue, glottis, or larynx), dyspnea, and throat closing have been reported and may be fatal.
- Concomitant administration of strong cytochrome P450 (CYP 3A) enzyme inhibitors (e.g., ketoconazole, itraconazole, nefazodone, lopinavir, ritonavir) [see Warnings and Precautions (5.7), Drug Interactions (7.1)].
5 WARNINGS AND PRECAUTIONS
5.1 Risks from Concomitant Use with Opioids
Concomitant use of benzodiazepines, including Halcion, and opioids may result in profound sedation, respiratory depression, coma, and death. Because of these risks, reserve concomitant prescribing of these drugs for use in patients for whom alternative treatment options are inadequate.
Observational studies have demonstrated that concomitant use of opioid analgesics and benzodiazepines increases the risk of drug-related mortality compared to use of opioids alone. If a decision is made to prescribe Halcion concomitantly with opioids, prescribe the lowest effective dosages and minimum durations of concomitant use, and follow patients closely for signs and symptoms of respiratory depression and sedation. In patients already receiving an opioid analgesic, prescribe a lower initial dose of Halcion than indicated in the absence of an opioid and titrate based on clinical response. If an opioid is initiated in a patient already taking Halcion, prescribe a lower initial dose of the opioid and titrate based upon clinical response.
Advise both patients and caregivers about the risks of respiratory depression and sedation when Halcion is used with opioids. Advise patients not to drive or operate heavy machinery until the effects of concomitant use with the opioid have been determined [see Drug Interactions (7.1)].
5.2 Persistent or Worsening Insomnia
Since sleep disturbances may be the presenting manifestation of a physical and/or psychiatric disorder, symptomatic treatment of insomnia should be initiated only after a careful evaluation of the patient. The failure of insomnia to remit after 7 to 10 days of treatment may indicate the presence of a primary psychiatric and/or medical illness that should be evaluated. Worsening of insomnia or the emergence of new thinking or behavior abnormalities may be the consequence of an unrecognized psychiatric or physical disorder. Such findings have emerged during the course of treatment with sedative-hypnotic drugs.
5.3 "Sleep-driving" and Other Complex Behaviors
Complex behaviors such as "sleep-driving" (i.e., driving while not fully awake after ingestion of a sedative-hypnotic, with amnesia for the event) have been reported with Halcion use. These events can occur in sedative-hypnotic-naïve as well as in sedative-hypnotic-experienced persons. Although behaviors such as sleep-driving may occur with sedative-hypnotics alone at recommended dosages, the use of alcohol and other central nervous system (CNS) depressants with sedative-hypnotics appears to increase the risk of such behaviors, as does the use of sedative-hypnotics at doses exceeding the maximum recommended dose. Due to the risk to the patient and the community, discontinuation of sedative-hypnotics should be strongly considered for patients who report a "sleep-driving" episode.
Other complex behaviors (e.g., preparing and eating food, making phone calls, or having sex) have been reported in patients who are not fully awake after taking a sedative-hypnotic, including Halcion. As with sleep-driving, patients usually do not remember these events.
5.4 Central Nervous System Manifestations
An increase in daytime anxiety has been reported for Halcion after as few as 10 days of continuous use. In some patients this may be a manifestation of interdose withdrawal. If increased daytime anxiety is observed during treatment, discontinuation of treatment may be advisable.
A variety of abnormal thinking and behavior changes have been reported to occur in association with the use of benzodiazepine hypnotics including Halcion. Some of these changes may be characterized by decreased inhibition, e.g., aggressiveness and extroversion that seem excessive, similar to that seen with alcohol and other CNS depressants (e.g., sedative/hypnotics). Other kinds of behavioral changes have also been reported, for example, bizarre behavior, agitation, hallucinations, depersonalization. In primarily depressed patients, the worsening of depression, including suicidal thinking, has been reported in association with the use of benzodiazepines [see Warnings and Precautions (5.8)].
Some adverse reactions reported in association with the use of Halcion such as drowsiness, dizziness, light-headedness, and amnesia appear to be dose related. More serious behavioral phenomena such as confusion, bizarre or abnormal behavior, agitation, and hallucinations may also be dose related, but this evidence is inconclusive. Therapy should be initiated at the lowest effective dose [see Dosage and Administration (2.1)].
It can rarely be determined with certainty whether a particular instance of the abnormal behaviors listed above is drug induced, spontaneous in origin, or a result of an underlying psychiatric or physical disorder. Nonetheless, the emergence of any new behavioral sign or symptom of concern requires careful and immediate evaluation.
Anterograde amnesia of varying severity and paradoxical reactions have been reported following recommended dosages of Halcion. Data from several sources suggest that anterograde amnesia may occur at a higher rate with Halcion than with other benzodiazepine hypnotics. Because HALCION can cause drowsiness and a decreased level of consciousness, patients, particularly the elderly, are at higher risk of falls.
Cases of "traveler's amnesia" have been reported by individuals who have taken Halcion to induce sleep while traveling, such as during an airplane flight. In some of these cases, insufficient time was allowed for the sleep period prior to awakening and before beginning activity. Also, the concomitant use of alcohol may have been a factor in some cases.
5.5 Effects on Driving and Operating Heavy Machinery
Due to its depressant CNS effects, patients receiving Halcion should be cautioned against engaging in hazardous occupations requiring complete mental alertness such as operating machinery or driving a motor vehicle. For the same reason, patients should be cautioned about the concomitant use of alcohol and other CNS depressant drugs during treatment with Halcion.
5.6 Triazolam Interaction with Drugs that Inhibit Metabolism via Cytochrome P450 3A
The initial step in triazolam metabolism is hydroxylation catalyzed by CYP 3A. Drugs that inhibit this metabolic pathway may have a profound effect on the clearance of triazolam.
Strong CYP 3A Inhibitors
Halcion is contraindicated in patients receiving strong inhibitors of CYP 3A such as ketoconazole, itraconazole, nefazodone, ritonavir, indinavir, nelfinavir, saquinavir, and lopinavir [see Contraindications (4), Drug Interactions (7.1)].
Moderate and Weak CYP 3A Inhibitors
Halcion should be used with caution in patients receiving moderate or weak inhibitors of CYP 3A. If coadministered, consider dose reduction of Halcion.
Coadministration of erythromycin increased the maximum plasma concentration, decreased clearance and increased half-life of triazolam [see Drug Interactions (7.1), Clinical Pharmacology (12.3)]; caution and consideration of appropriate triazolam dose reduction are recommended. Similar caution should be observed during coadministration with clarithromycin and other macrolide antibiotics.
5.7 Patients with Depression
Benzodiazepines may worsen depression. Consequently, appropriate precautions (e.g., limiting the total prescription size and increased monitoring for suicidal ideation) should be considered in patients with depression.
5.8 Tolerance/Withdrawal Phenomena
Some loss of effectiveness or adaptation to the sleep inducing effects of benzodiazepines, including Halcion, may develop after nightly use for more than a few weeks and there may be a degree of dependence that develops. Withdrawal phenomena with HALCION have included: 1) increased wakefulness during the last third of the night, and 2) the appearance of increased signs of daytime anxiety or nervousness.
Withdrawal effects can occur after discontinuing these drugs following use for only a week or two, but may be more common and more severe after longer periods of continuous use. A phenomena known as 'rebound insomnia' may occur after stopping HALCION. That is, on the first few nights after the drug is stopped, insomnia is actually worse than before the sleeping pill was given.
Other withdrawal phenomena following abrupt stopping of benzodiazepine sleeping pills range from mild unpleasant feelings to a major withdrawal syndrome which may include abdominal and muscle cramps, vomiting, sweating, tremor, and convulsions.
5.9 Neonatal Sedation and Withdrawal Syndrome
Use of Halcion during the later stages of pregnancy can result in sedation (respiratory depression, lethargy, hypotonia) and withdrawal symptoms (hyperreflexia, irritability, restlessness, tremors, inconsolable crying, and feeding difficulties) in the neonate. Observe newborns for signs of sedation and neonatal withdrawal syndrome and manage accordingly [see Use in Specific Populations (8.1)].
6 ADVERSE REACTIONS
The following serious adverse reactions are discussed in greater detail in other sections:
- Risks from Concomitant Use with Opioids [see Warnings and Precautions (5.1)]
- Persistent or Worsening Insomnia [see Warnings and Precautions (5.2)]
- "Sleep-driving" and Other Complex Behaviors [see Warnings and Precautions (5.3)]
- Central Nervous System Manifestations [see Warnings and Precautions (5.4)]
- Effects on Driving and Operating Heavy Machinery [see Warnings and Precautions (5.5)]
- Patients with Depression [see Warnings and Precautions (5.7)]
- Tolerance/Withdrawal Phenomena [see Warnings and Precautions (5.8)]
- Compromised Respiratory Function [see Warnings and Precautions (5.10)]
6.1 Clinical Trials Experience
Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.
The incidences cited below are estimates of clinical reactions among 1003 subjects who participated in the short term (duration of 1 to 42 days) placebo-controlled clinical trials of Halcion.
Adverse reactions leading to discontinuation in two multi-dose placebo controlled clinical trials include coordination disorders, drowsiness, grogginess, somnolence, depression, restlessness, dizziness, lightheadedness, headache, nausea, visual disturbance, nervousness, abdominal distress, bladder trouble, aching limbs, backache, and blepharitis.
% Patients Reporting
% Patients Reporting
|Central Nervous System|
In addition to the common reactions enumerated above in Table1, the following adverse reactions have been reported at an incidence of 0.9% to 0.5%: euphoria, tachycardia, tiredness, confusional states/memory impairment, cramps/pain, depression, and visual disturbances.
Adverse reactions reported at an incidence less than 0.5% include: constipation, taste alterations, diarrhea, dry mouth, dermatitis/allergy, dreaming/nightmares, insomnia, paresthesia, tinnitus, dysesthesia, weakness, congestion, and death from hepatic failure in a patient also receiving diuretic drugs.
6.2 Postmarketing Experience
The following adverse reactions have been identified during post-approval use of Halcion. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.
General disorders and administration site conditions: Paradoxical drug reaction, chest pain and fatigue
Gastrointestinal disorders: Tongue discomfort, glossitis, stomatitis
Hepatobiliary disorders: Jaundice
Injury, poisoning and procedural complications: Fall
Metabolism and nutrition disorders: Anorexia
Nervous system disorders: Anterograde amnesia, altered state of consciousness, dystonia, sedation, syncope, dysarthria and muscle spasticity
Psychiatric disorders: Confusional state (disorientation, derealisation, depersonalization), mania, agitation, restlessness, irritability, sleep disorder and libido disorder, hallucination, delusion, aggression, somnambulism, and abnormal behavior
Renal and urinary disorders: Urinary retention and urinary incontinence
Reproductive system and breast disorders: Menstruation irregular
Skin and subcutaneous tissue disorders: Pruritis
7 DRUG INTERACTIONS
7.1 Drugs Having Clinically Important Interactions with Halcion
Table 2 includes clinically significant drug interactions with Halcion [see Clinical Pharmacology (12.3)].
|Clinical implication||The concomitant use of benzodiazepines and opioids increases the risk of respiratory depression because of actions at different receptor sites in the CNS that control respiration. Benzodiazepines interact at GABAA sites and opioids interact primarily at mu receptors. When benzodiazepines and opioids are combined, the potential for benzodiazepines to significantly worsen opioid-related respiratory depression exists.|
|Prevention or management||Limit dosage and duration of concomitant use of Halcion and opioids, and monitor patients closely for respiratory depression and sedation [see Warnings and Precautions (5.1)].|
|Examples||Morphine, buprenorphine, hydromorphone, oxymorphone, oxycodone, fentanyl, methadone, alfentanil, butorphanol, codeine, dihydrocodeine, meperidine, pentazocine, remifentanil, sufentanil, tapentadol, tramadol.|
|Clinical implication||Triazolam produces additive CNS depressant effects when co-administered with other CNS depressants.|
|Prevention or management||Limit dosage and duration of Halcion during concomitant use with CNS depressants.|
|Examples||Psychotropic medications, anticonvulsants, antihistamines, ethanol, and other drugs which themselves produce CNS depression.|
|Strong Inhibitors of CYP 3A|
|Clinical implication||Concomitant use of Halcion with strong CYP3A inhibitors has a profound effect on the clearance of Halcion, resulting in increased concentrations of triazolam and increased risk of adverse reactions [see Clinical Pharmacology (12.3)].|
|Prevention or management||Do not administer Halcion with a strong CYP3A4 inhibitor [see Contraindications (4), Warnings and Precautions (5.7)].|
|Examples||Ketoconazole, clarithromycin, grapefruit juice, itraconazole, nefazodone, and several HIV protease inhibitors (e.g. ritonavir, indinavir, nelfinavir, saquinavir and lopinavir).|
|Moderate and Weak Inhibitors of CYP 3A|
|Clinical implication||Concomitant use of Halcion with moderate or weak inhibitors of CYP3A inhibitors may increase the concentrations of Halcion, resulting in increased risk of adverse reactions [see Clinical Pharmacology (12.3)].|
|Prevention or management||Use with caution and consider appropriate dose reduction of HALCION when coadministered with moderate and weak CYP3A inhibitors [see Warnings and Precautions (5.7)].|
|Examples||Macrolide antibiotics (such as erythromycin), cimetidine, isoniazid, oral contraceptives, ranitidine.|
|Interactions Based on Experience with Other Benzodiazepines or in vitro Studies with Triazolam|
|Clinical implication||Available data from clinical studies of benzodiazepines other than triazolam, from in vitro studies with triazolam, or from in vitro studies with benzodiazepines other than triazolam suggest a possible drug interaction with triazolam [see Clinical Pharmacology (12.3)].|
|Prevention or management||Caution is recommended during coadministration of Halcion with any of these drugs. [see Warnings and Precautions (5.7)].|
|Examples||Fluvoxamine, diltiazem, verapamil, sertraline, paroxetine, ergotamine, cyclosporine, amiodarone, nicardipine, and nifedipine.|
8 USE IN SPECIFIC POPULATIONS
Pregnancy Exposure Registry
There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to Halcion during pregnancy. Healthcare providers are encouraged to register patients by calling the National Pregnancy Registry for Other Psychiatric Medications at 1-866-961-2388 or visiting online at https://womensmentalhealth.org/clinical-and-research-programs/pregnancyregistry/othermedications/.
Infants born to mothers using benzodiazepines during the later stages of pregnancy have been reported to experience symptoms of sedation and neonatal withdrawal (see Clinical Considerations) [see Warnings and Precautions (5.9)]. At this time, there is no clear evidence that triazolam exposure in early pregnancy can cause major birth defects (see Data).
The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2–4% and 15–20%, respectively.
Fetal/Neonatal adverse reactions
Benzodiazepines cross the placenta and may produce respiratory depression and sedation in neonates. Monitor neonates exposed to Halcion during pregnancy and labor for signs of sedation, respiratory depression, withdrawal, and feeding problems and manage accordingly [see Warnings and Precautions (5.9)].
Published data from observational studies on the use of benzodiazepines during pregnancy do not report a clear association with benzodiazepines and major birth defects. Although early studies reported an increased risk of congenital malformations with diazepam and chlordiazepoxide, there was no consistent pattern noted. In addition, the majority of more recent case-control and cohort studies of benzodiazepine use during pregnancy, which were adjusted for confounding exposures to alcohol, tobacco and other medications, have not confirmed these findings. At this time, there is no clear evidence that triazolam exposure in early pregnancy can cause major birth defects.
Infants exposed to benzodiazepines during the late third trimester of pregnancy or during labor have been reported to exhibit sedation and neonatal withdrawal symptoms.
Oral administration of triazolam to pregnant rats and rabbits during the period of organogenesis caused skeletal developmental changes (variations and malformations) at maternally toxic doses in rats and at doses in rats and rabbits which are approximately equal to or greater than 200 times the maximum recommended human dose (MRHD) of 0.5 mg/day based on mg/m2 body surface area. Oral administration of triazolam to male and female rats before mating, and continuing during gestation and lactation did not result in embryotoxicity at doses up to approximately 100 times the MRHD based on mg/m2 body surface area, but did cause an increase in the number of stillbirths and postnatal pup mortalities at doses greater than or equal to approximately 40 times the MRHD based mg/m2 body surface area. 14C-triazolam was administered orally to pregnant mice. Drug-related material appeared uniformly distributed in the fetus with 14C concentrations approximately the same as in the brain of the mother.
There are no data on the presence of triazolam in human milk or the effects on milk production. There are reports of central nervous system depression (sedation, respiratory depression), withdrawal symptoms, and feeding problems in infants who are breastfed by mothers taking benzodiazepines (see Clinical Considerations).
Triazolam and its metabolites are present in the milk of lactating rats (see Data). When a drug is present in animal milk, it is likely that the drug will be present in human milk. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for HALCION and any potential adverse effects on the breastfed infant from HALCION or from the underlying maternal condition.
Infants exposed to HALCION through breast milk should be monitored for sedation, respiratory depression, withdrawal symptoms, and feeding problems. A lactating woman may consider interrupting breastfeeding and pumping and discarding breast milk during treatment and for 28 hours (approximately 5 elimination half-lives) after HALCION administration in order to minimize drug exposure to a breast fed infant.
8.4 Pediatric Use
Safety and effectiveness of Halcion have not been established in pediatric patients.
8.5 Geriatric Use
Elderly patients exhibit higher plasma triazolam concentrations due to reduced clearance as compared with younger subjects at the same dose. Because elderly patients are especially susceptible to dose related adverse reactions and to minimize oversedation, the smallest effective dose should be used [see Dosage and Administration (2.2), Clinical Pharmacology (12.3)].
9 DRUG ABUSE AND DEPENDENCE
Abuse and addiction are separate and distinct from physical dependence and tolerance. Abuse is characterized by misuse of the drug for non-medical purposes, often in combination with other psychoactive substances. Physical dependence is a state of adaptation that is manifested by a specific withdrawal syndrome that can be produced by abrupt cessation, rapid dose reduction, decreasing blood level of the drug and/or administration of an antagonist. Tolerance is a state of adaptation in which exposure to a drug induces changes that result in a diminution of one or more of the drug's effects over time. Tolerance may occur to both the desired and undesired effects of drugs and may develop at different rates for different effects.
Addiction is a primary, chronic, neurobiological disease with genetic, psychosocial, and environmental factors influencing its development and manifestations. It is characterized by behaviors that include one or more of the following: impaired control over drug use, compulsive use, continued use despite harm, and craving. Drug addiction is a treatable disease, utilizing a multidisciplinary approach, but relapse is common.
Addiction-prone individuals (e.g. those with a history of drug addiction or alcoholism) should be under careful surveillance when receiving HALCION because of increased risk of abuse and dependence.
Withdrawal symptoms, including: convulsions, tremor, abdominal and muscle cramps, vomiting, sweating, dysphoria, perceptual disturbances, and insomnia have occurred following abrupt discontinuance of benzodiazepines, including Halcion. The more severe symptoms are usually associated with higher dosages and longer usage, although patients at recommended dosages given for as few as 1 to 2 weeks can also have withdrawal symptoms and in some patients there may be withdrawal symptoms (daytime anxiety, agitation) between nightly doses [see Warnings and Precautions (5.9)]. Consequently, abrupt discontinuation should be avoided and a gradual dosage tapering schedule is recommended in any patient taking more than the lowest dose for more than a few weeks. The recommendation for tapering is particularly important in any patient with a history of seizure.
The risk of dependence is increased in patients with a history of alcoholism, drug abuse, or in patients with marked personality disorders. Such dependence-prone individuals should be under careful surveillance when receiving Halcion. As with all hypnotics, repeat prescriptions should be limited to those who are under medical supervision.
Manifestations of overdosage with Halcion include somnolence, confusion, impaired coordination, slurred speech, and ultimately, coma. Respiratory depression and apnea have been reported with overdosages of Halcion. Seizures have been reported after overdosages.
Death has been reported in association with overdoses of Halcion. In addition, fatalities have been reported in patients who have overdosed with a combination of a single benzodiazepine, including Halcion, and alcohol; benzodiazepine and alcohol levels seen in some of these cases have been lower than those usually associated with reports of fatality with either substance alone.
Respiration, pulse, and blood pressure should be monitored and supported by general measures when necessary. Immediate gastric lavage should be performed. An adequate airway should be maintained. Intravenous fluids may be administered.
Flumazenil may be useful in situations when an overdose with a benzodiazepine is known or suspected. Prior to the administration of flumazenil, necessary measures should be instituted to secure airway, ventilation and intravenous access. Flumazenil is intended as an adjunct to, not as a substitute for, proper management of benzodiazepine overdose. Patients treated with flumazenil should be monitored for resedation, respiratory depression, and other residual benzodiazepine effects for an appropriate period after treatment. The prescriber should be aware of a risk of seizure in association with flumazenil treatment, particularly in long-term benzodiazepine users and in cyclic antidepressant overdose. The complete flumazenil package insert including Contraindications and Warnings and Precautions should be consulted prior to use.
Hemodialysis and forced diuresis are probably of little value. As with the management of intentional overdosage with any drug, the physician should bear in mind that multiple agents may have been ingested by the patient.
In case of an overdosage, consult a Certified Poison Control Center at 1-800-222-1222 for latest recommendations.
Halcion Tablets contains triazolam, a triazolobenzodiazepine.
Triazolam is a white crystalline powder, soluble in alcohol and poorly soluble in water. It has a molecular weight of 343.21.
The chemical name for triazolam is 8-chloro-6-(o-chlorophenyl)-1-methyl-4H-s-triazolo-[4,3-α] [1,4] benzodiazepine.
The structural formula is represented below:
Each Halcion tablet, for oral administration, contains 0.25 mg of triazolam.
Inactive ingredients: cellulose, corn starch, docusate sodium, FD&C Blue No. 2, lactose, magnesium stearate, silicon dioxide, sodium benzoate.
12 CLINICAL PHARMACOLOGY
12.1 Mechanism of Action
Triazolam is a benzodiazepine. Triazolam exerts its effect for the short-term treatment of insomnia through binding to the benzodiazepine site of the gamma-aminobutyric acid-A (GABAA) receptors in the brain and enhances GABA-mediated synaptic inhibition.
Peak plasma levels of triazolam are reached within 2 hours following oral administration. Following recommended doses of Halcion, triazolam peak plasma levels in the range of 1 to 6 ng/mL are seen. The plasma levels achieved are proportional to the dose given. In normal subjects treated for 7 days with four times the recommended dosage, there was no evidence of altered systemic bioavailability, rate of elimination, or accumulation.
Extremely high concentrations of triazolam do not displace bilirubin bound to human serum albumin in vitro.
Triazolam has a mean plasma elimination half-life in the range of 1.5 to 5.5 hours.
The initial step in triazolam metabolism is cytochrome P450 3A (CYP 3A)-mediated hydroxylation to form 1-hydroxytriazolam and 4-hydroxytriazolam, which are subsequently conjugated to form glucuronides.
Triazolam and its metabolites, principally as conjugated glucuronides which are presumably inactive, are excreted primarily in the urine. Only small amounts of unmetabolized triazolam appear in the urine. The two primary metabolites accounted for 79.9% of urinary excretion. Urinary excretion appeared to be biphasic in its time course.
In a study of elderly (62 to 83 years old) versus younger subjects (21 to 41 years old) who received triazolam at the same dose levels (0.125 mg and 0.25 mg), the elderly experienced both greater sedation and impairment of psychomotor performance. These effects resulted largely from higher plasma concentrations of triazolam in the elderly.
Drug Interaction Studies
The effect of other drugs on triazolam:
Coadministration of erythromycin increased the maximum plasma concentration of triazolam by 46%, decreased clearance by 53%, and increased half-life by 35%.
Coadministration of cimetidine increased the maximum plasma concentration of triazolam by 51%, decreased clearance by 55%, and increased half-life by 68%.
Coadministration of isoniazid increased the maximum plasma concentration of triazolam by 20%, decreased clearance by 42%, and increased half-life by 31%.
Coadministration of oral contraceptives increased maximum plasma concentration by 6%, decreased clearance by 32%, and increased half-life by 16%.
Coadministration of grapefruit juice increased the maximum plasma concentration of triazolam by 25%, increased the area under the concentration curve by 48%, and increased half-life by 18%.
Coadministration of ranitidine increased the maximum plasma concentration of triazolam by 30%, increased the area under the concentration curve by 27%, and increased half-life by 3.3%. Caution is recommended during coadministration with triazolam. Available data from clinical studies of benzodiazepines other than triazolam suggest a possible drug interaction with triazolam for the following: fluvoxamine, diltiazem, and verapamil. Data from in vitro studies of triazolam suggest a possible drug interaction with triazolam for the following: sertraline and paroxetine. Data from in vitro studies of benzodiazepines other than triazolam suggest a possible drug interaction with triazolam for the following: ergotamine, cyclosporine, amiodarone, nicardipine, and nifedipine.
The effect of triazolam on other drugs:
13 NONCLINICAL TOXICOLOGY
13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility
No evidence of carcinogenic potential was observed in rats or mice administered triazolam in the diet for 24-months at doses greater than or equal to 900 times the MRHD of 0.5 mg, based on mg/m2 body surface area.
Triazolam was not mutagenic in the in vitro Ames bacterial reverse mutation assay, and no DNA damage was observed in an in vitro alkaline elution assay in Chinese hamster lung fibroblast cells.
Impairment of Fertility
Female rats were administered triazolam in the diet for 14 days before cohabitation, during gestation, and until 21 days post parturition, and male rats for 60 days before cohabitation. No effects on mating or fertility were observed in rats up to 5 mg/kg/day which is approximately 100 times the MRHD of 0.5 mg/day, based on mg/m2 body surface area.
16 HOW SUPPLIED/STORAGE AND HANDLING
Halcion is supplied as a powder blue, elliptical, scored tablet in the following strengths and package configurations:
|Package Configuration||Tablet Strength (mg)||NDC|
Unit Dose (100)
|0.25 mg||NDC 0009-0017-55||HALCION 0.25|
|Bottles of 10||0.25 mg||NDC 0009-0017-58||HALCION 0.25|
17 PATIENT COUNSELING INFORMATION
Advise the patient to read the FDA-approved patient labeling (Medication Guide).
Risks from Concomitant Use with Opioids
Advise both patients and caregivers about the risks of potentially fatal respiratory depression and sedation when Halcion is used with opioids and not to use such drugs concomitantly unless supervised by a healthcare provider. Advise patients not to drive or operate heavy machinery until the effects of concomitant use with the opioid have been determined [see Warnings and Precautions (5.1), Drug Interactions (7.1)].
"Sleep-driving" and Other Complex Behaviors
There have been reports of people getting out of bed after taking a sedative-hypnotic and driving their cars while not fully awake, often with no memory of the event. Advise patients to report similar experiences to their healthcare provider immediately, since "sleep-driving" can be dangerous. This behavior is more likely to occur when sedative-hypnotics are taken with alcohol or other CNS depressants [see Warnings and Precautions (5.3)]. Other complex behaviors (e.g., preparing and eating food, making phone calls, or having sex) have been reported in patients who are not fully awake after taking a sedative hypnotic. As with sleep-driving, patients usually do not remember these events.
Advise patients that increased drowsiness and decreased consciousness may increase the risk of falls in some patients.
Effects on Driving and Operating Heavy Machinery
Caution patients against driving a motor vehicle or operating heavy machinery until the effects of taking Halcion are determined due to its CNS depressant effects. Also advise patients to avoid the use of alcohol or other CNS depressants while taking Halcion [see Warnings and Precautions (5.6)].
Patients with Depression
Advise patients, their families and caregivers to look out for any signs of suicidality or worsening depression, and to inform the patient's prescriber or healthcare provider immediately [see Warnings and Precautions (5.8)].
Advise patients to inform their healthcare provider of all medicines they take, including prescription and nonprescription medicines, vitamins and herbal supplements [see Drug Interactions (7.1, 7.2)].
Advise patients to avoid eating grapefruit or drinking grapefruit juice while taking Halcion [see Drug Interactions (7.2)].
Benzodiazepines cross the placenta and may produce respiratory depression and sedation in neonates. Advise mothers using Halcion to monitor neonates for signs of sedation, respiratory depression, withdrawal, and feeding problems [see Warnings and Precautions (5.9), Use in Specific Populations (8.1)].
Advise mothers using benzodiazepines to monitor neonates for signs of sedation, respiratory depression, withdrawal symptoms, and feeding problems. A lactating woman may consider pumping and discarding breastmilk during treatment and for 28 hours after Halcion administration to minimize drug exposure to a breastfed infant [see Use in Specific Populations (8.2)].