The information included in the subsection on Adverse Events Observed in Short-Term,
Placebo-Controlled Trials with XANAX XR Tablets is based on pooled data of five
6- and 8-week placebo-controlled clinical studies in panic disorder.
Adverse event reports were elicited either by general inquiry or by checklist,
and were recorded by clinical investigators using terminology of their own choosing.
The stated frequencies of adverse events represent the proportion of individuals
who experienced, at least once, a treatment-emergent adverse event of the type
listed. An event was considered treatment emergent if it occurred for the first
time or worsened during therapy following baseline evaluation. In the tables
and tabulations that follow, standard MedDRA terminology (version 4.0) was used
to classify reported adverse events.
Adverse Events Observed in Short-Term, Placebo-Controlled Trials of XANAX
XR
Adverse Events Reported as Reasons for Discontinuation of Treatment in Placebo-Controlled
Trials
Approximately 17% of the 531 patients who received XANAX XR in placebo-controlled
clinical trials for panic disorder had at least one adverse event that led to
discontinuation compared to 8% of 349 placebo-treated patients. The most common
events leading to discontinuation and considered to be drug-related (ie, leading
to discontinuation in at least 1% of the patients treated with XANAX XR at a
rate at least twice that of placebo) are shown in the following table.
Common Adverse Events Leading to Discontinuation of Treatment
in Placebo-Controlled Trials
| System Organ Class/Adverse Event |
Percentage of Patients Discontinuing Due to
Adverse Events |
XANAX XR
(n=531) |
Placebo
(n=349) |
| Nervous system disorders |
| Sedation |
7.5 |
0.6 |
| Somnolence |
3.2 |
0.3 |
| Dysarthria |
2.1 |
0 |
| Coordination abnormal |
1.9 |
0.3 |
| Memory impairment |
1.5 |
0.3 |
| General disorders/administration site conditions |
| Fatigue |
1.7 |
0.6 |
| Psychiatric disorders |
| Depression |
2.5 |
1.2 |
Adverse Events Occurring at an Incidence of 1% or More Among Patients Treated
with XANAX XR
The prescriber should be aware that adverse event incidence cannot be used
to predict the incidence of adverse events in the course of usual medical practice
where patient characteristics and other factors differ from those which prevailed
in the clinical trials. Similarly, the cited frequencies cannot be compared
with event incidence obtained from other clinical investigations involving different
treatments, uses, and investigators. The cited values, however, do provide the
prescribing physician with some basis for estimating the relative contribution
of drug and non-drug factors to the adverse event incidence rate in the population
studied.
The following table shows the incidence of treatment-emergent adverse events
that occurred during 6- to 8-week placebo-controlled trials in 1% or more of
patients treated with XANAX XR where the incidence in patients treated with
XANAX XR was greater than the incidence in placebo-treated patients. The most
commonly observed adverse events in panic disorder patients treated with XANAX
XR (incidence of 5% or greater and at least twice the incidence in placebo patients)
were: sedation, somnolence, memory impairment, dysarthria, coordination abnormal,
ataxia, libido decreased (see table).
Treatment-Emergent Adverse Events: Incidence in Short-Term,
Placebo-Controlled Clinical Trials with XANAX XR
| System Organ Class/Adverse Event |
Percentage of Patients Reporting Adverse Event |
XANAX XR
(n=531) |
Placebo
(n=349) |
| Nervous system disorders |
| Sedation |
45.2 |
22.6 |
| Somnolence |
23.0 |
6.0 |
| Memory impairment |
15.4 |
6.9 |
| Dysarthria |
10.9 |
2.6 |
| Coordination abnormal |
9.4 |
0.9 |
| Mental impairment |
7.2 |
5.7 |
| Ataxia |
7.2 |
3.2 |
| Disturbance in attention |
3.2 |
0.6 |
| Balance impaired |
3.2 |
0.6 |
| Paresthesia |
2.4 |
1.7 |
| Dyskinesia |
1.7 |
1.4 |
| Hypoesthesia |
1.3 |
0.3 |
| Hypersomnia |
1.3 |
0 |
| General disorders/administration site conditions |
| Fatigue |
13.9 |
9.2 |
| Lethargy |
1.7 |
0.6 |
| Infections and infestations |
| Influenza |
2.4 |
2.3 |
| Upper respiratory tract infections |
1.9 |
1.7 |
| Psychiatric disorders |
| Depression |
12.1 |
9.2 |
| Libido decreased |
6.0 |
2.3 |
| Disorientation |
1.5 |
0 |
| Confusion |
1.5 |
0.9 |
| Depressed mood |
1.3 |
0.3 |
| Anxiety |
1.1 |
0.6 |
| Metabolism and nutrition disorders |
| Appetite decreased |
7.3 |
7.2 |
| Appetite increased |
7.0 |
6.0 |
| Anorexia |
1.5 |
0 |
| Gastrointestinal disorders |
| Dry mouth |
10.2 |
9.7 |
| Constipation |
8.1 |
4.3 |
| Nausea |
6.0 |
3.2 |
| Pharyngolaryngeal pain |
3.2 |
2.6 |
| Investigations |
| Weight increased |
5.1 |
4.3 |
| Weight decreased |
4.3 |
3.7 |
| Injury, poisoning, and procedural complications |
| Road traffic accident |
1.5 |
0 |
| Reproductive system and breast disorders |
| Dysmenorrhea |
3.6 |
2.9 |
| Sexual dysfunction |
2.4 |
1.1 |
| Premenstrual syndrome |
1.7 |
0.6 |
| Musculoskeletal and connective tissue disorders |
| Arthralgia |
2.4 |
0.6 |
| Myalgia |
1.5 |
1.1 |
| Pain in limb |
1.1 |
0.3 |
| Vascular disorders |
| Hot flushes |
1.5 |
1.4 |
| Respiratory, thoracic, and mediastinal disorders |
| Dyspnea |
1.5 |
0.3 |
| Rhinitis allergic |
1.1 |
0.6 |
| Skin and subcutaneous tissue disorders |
| Pruritis |
1.1 |
0.9 |
Other Adverse Events Observed During the Premarketing Evaluation of XANAX
XR Tablets
Following is a list of MedDRA terms that reflect treatment-emergent adverse
events reported by 531 patients with panic disorder treated with XANAX XR. All
potentially important reported events are included except those already listed
in the above table or elsewhere in labeling, those events for which a drug cause
was remote, those event terms that were so general as to be uninformative, and
those events that occurred at rates similar to background rates in the general
population. It is important to emphasize that, although the events reported
occurred during treatment with XANAX XR, they were not necessarily caused by
the drug. Events are further categorized by body system and listed in order
of decreasing frequency according to the following definitions: frequent adverse
events are those occurring on 1 or more occasions in at least l/l00 patients;
infrequent adverse events are those occurring in less than l/100 patients but
at least l/1000 patients; rare events are those occurring in fewer than l/1000
patients.
Cardiac disorders: Frequent: palpitation; Infrequent: sinus
tachycardia
Ear and Labyrinth disorders: Frequent: Vertigo; Infrequent:
tinnitus, ear pain
Eye disorders: Frequent: blurred vision; Infrequent:
mydriasis, photophobia
Gastrointestinal disorders: Frequent: diarrhea, vomiting,
dyspepsia, abdominal pain; Infrequent: dysphagia, salivary hypersecretion
General disorders and administration site conditions: Frequent:
malaise, weakness, chest pains; Infrequent: fall, pyrexia, thirst, feeling
hot and cold, edema, feeling jittery, sluggishness, asthenia, feeling drunk,
chest tightness, increased energy, feeling of relaxation, hangover, loss of
control of legs, rigors
Musculoskeletal and connective tissue disorders: Frequent:
back pain, muscle cramps, muscle twitching
Nervous system disorders: Frequent: headache, dizziness,
tremor; Infrequent: amnesia, clumsiness, syncope, hypotonia, seizures,
depressed level of consciousness, sleep apnea syndrome, sleep talking, stupor
Psychiatric system disorders: Frequent: irritability,
insomnia, nervousness, derealization, libido increased, restlessness, agitation,
depersonalization, nightmare; Infrequent: abnormal dreams, apathy, aggression,
anger, bradyphrenia, euphoric mood, logorrhea, mood swings, dysphonia, hallucination,
homicidal ideation, mania, hypomania, impulse control, psychomotor retardation,
suicidal ideation
Renal and urinary disorders: Frequent: difficulty in micturition;
Infrequent: urinary frequency, urinary incontinence
Respiratory, thoracic, and mediastinal disorders: Frequent: nasal
congestion, hyperventilation; Infrequent: choking sensation, epistaxis,
rhinorrhea
Skin and subcutaneous tissue disorders: Frequent: sweating
increased; Infrequent: clamminess, rash, urticaria
Vascular disorders: Infrequent: hypotension
The categories of adverse events reported in the clinical development program
for XANAX Tablets in the treatment of panic disorder differ somewhat from those
reported for XANAX XR Tablets because the clinical trials with XANAX Tablets
and XANAX XR Tablets used different standard medical nomenclature for reporting
the adverse events. Nevertheless, the types of adverse events reported in the
clinical trials with XANAX Tablets were generally the same as those reported
in the clinical trials with XANAX XR Tablets.
Discontinuation-Emergent Adverse Events Occurring at an Incidence of 5% or
More Among Patients Treated with XANAX XR
The following table shows the incidence of discontinuation-emergent adverse
events that occurred during short-term, placebo-controlled trials in 5% or more
of patients treated with XANAX XR where the incidence in patients treated with
XANAX XR was two times greater than the incidence in placebo-treated patients.
Discontinuation-Emergent Symptoms: Incidence in Short-Term,
Placebo-Controlled Trials with XANAX XR
| System Organ Class/Adverse Event |
Percentage of Patients Reporting Adverse Event |
XANAX XR
(n=422) |
Placebo
(n=261) |
| Nervous system disorders |
| Tremor |
28.2 |
10.7 |
| Headache |
26.5 |
12.6 |
| Hypoesthesia |
7.8 |
2.3 |
| Paraesthesia |
7.1 |
2.7 |
| Psychiatric disorders |
| Insomnia |
24.2 |
9.6 |
| Nervousness |
21.8 |
8.8 |
| Depression |
10.9 |
5.0 |
| Derealization |
8.0 |
3.8 |
| Anxiety |
7.8 |
2.7 |
| Depersonalization |
5.7 |
1.9 |
| Gastrointestinal disorders |
| Diarrhea |
12.1 |
3.1 |
| Respiratory, thoracic and mediastinal disorders |
| Hyperventilation |
8.5 |
2.7 |
| Metabolism and nutrition disorders |
| Appetite decreased |
9.5 |
3.8 |
| Musculosketal and connective tissue disorders |
| Muscle twitching |
7.4 |
2.7 |
| Vascular disorders |
|
|
| Hot flushes |
5.9 |
2.7 |
There have also been reports of withdrawal seizures upon rapid decrease or
abrupt discontinuation of alprazolam (see WARNINGS).
To discontinue treatment in patients taking XANAX XR Tablets, the dosage should
be reduced slowly in keeping with good medical practice. It is suggested that
the daily dosage of XANAX XR Tablets be decreased by no more than 0.5 mg every
three days (see DOSAGE AND ADMINISTRATION). Some patients may benefit
from an even slower dosage reduction. In a controlled postmarketing discontinuation
study of panic disorder patients which compared this recommended taper schedule
with a slower taper schedule, no difference was observed between the groups
in the proportion of patients who tapered to zero dose; however, the slower
schedule was associated with a reduction in symptoms associated with a withdrawal
syndrome.
As with all benzodiazepines, paradoxical reactions such as stimulation, increased
muscle spasticity, sleep disturbances, hallucinations, and other adverse behavioral
effects such as agitation, rage, irritability, and aggressive or hostile behavior
have been reported rarely. In many of the spontaneous case reports of adverse
behavioral effects, patients were receiving other CNS drugs concomitantly and/or
were described as having underlying psychiatric conditions. Should any of the
above events occur, alprazolam should be discontinued. Isolated published reports
involving small numbers of patients have suggested that patients who have borderline
personality disorder, a prior history of violent or aggressive behavior, or
alcohol or substance abuse may be at risk for such events. Instances of irritability,
hostility, and intrusive thoughts have been reported during discontinuation
of alprazolam in patients with posttraumatic stress disorder.
Post Introduction Reports
Various adverse drug reactions have been reported in association with the use
of XANAX Tablets since market introduction. The majority of these reactions
were reported through the medical event voluntary reporting system. Because
of the spontaneous nature of the reporting of medical events and the lack of
controls, a causal relationship to the use of XANAX Tablets cannot be readily
determined. Reported events include: liver enzyme elevations, hepatitis, hepatic
failure, Stevens-Johnson syndrome, hyperprolactinemia, gynecomastia, and galactorrhea.
Drug Abuse And Dependence
Physical and Psychological Dependence
Withdrawal symptoms similar in character to those noted with sedative/hypnotics
and alcohol have occurred following discontinuance of benzodiazepines, including
alprazolam. The symptoms can range from mild dysphoria and insomnia to a major
syndrome that may include abdominal and muscle cramps, vomiting, sweating, tremors,
and convulsions. Distinguishing between withdrawal emergent signs and symptoms
and the recurrence of illness is often difficult in patients undergoing dose
reduction. The long-term strategy for treatment of these phenomena will vary
with their cause and the therapeutic goal. When necessary, immediate management
of withdrawal symptoms requires re-institution of treatment at doses of alprazolam
sufficient to suppress symptoms. There have been reports of failure of other
benzodiazepines to fully suppress these withdrawal symptoms. These failures
have been attributed to incomplete cross-tolerance but may also reflect the
use of an inadequate dosing regimen of the substituted benzodiazepine or the
effects of concomitant medications.
While it is difficult to distinguish withdrawal and recurrence for certain
patients, the time course and the nature of the symptoms may be helpful. A withdrawal
syndrome typically includes the occurrence of new symptoms, tends to appear
toward the end of taper or shortly after discontinuation, and will decrease
with time. In recurring panic disorder, symptoms similar to those observed before
treatment may recur either early or late, and they will persist.
While the severity and incidence of withdrawal phenomena appear to be related
to dose and duration of treatment, withdrawal symptoms, including seizures,
have been reported after only brief therapy with alprazolam at doses within
the recommended range for the treatment of anxiety (eg, 0.75 to 4 mg/day). Signs
and symptoms of withdrawal are often more prominent after rapid decrease of
dosage or abrupt discontinuance. The risk of withdrawal seizures may be increased
at doses above 4 mg/day (see WARNINGS).
Patients, especially individuals with a history of seizures or epilepsy, should
not be abruptly discontinued from any CNS depressant agent, including alprazolam.
It is recommended that all patients on alprazolam who require a dosage reduction
be gradually tapered under close supervision (see WARNINGS
and DOSAGE AND ADMINISTRATION).
Psychological dependence is a risk with all benzodiazepines, including alprazolam.
The risk of psychological dependence may also be increased at doses greater
than 4 mg/day and with longer term use, and this risk is further increased in
patients with a history of alcohol or drug abuse. Some patients have experienced
considerable difficulty in tapering and discontinuing from alprazolam, especially
those receiving higher doses for extended periods. Addiction-prone individuals
should be under careful surveillance when receiving alprazolam. As with all
anxiolytics, repeat prescriptions should be limited to those who are under medical
supervision.
Controlled Substance Class
Alprazolam is a controlled substance under the Controlled Substance Act by
the Drug Enforcement Administration and XANAX XR Tablets have been assigned
to Schedule IV.