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)].