Serious cardiac events, including some that have been fatal, have occurred
following the use of 5-HT1 agonists. These events are extremely rare
and most have been reported in patients with risk factors predictive of CAD.
Events reported have included coronary artery vasospasm, transient myocardial ischemia, myocardial infarction, ventricular tachycardia, and ventricular fibrillation
(see CONTRAINDICATIONS, WARNINGS,
and PRECAUTIONS).
Incidence in Controlled Clinical Trials: The most common adverse events
were paresthesias, dizziness, drowsiness, malaise/fatigue, and throat/neck symptoms,
which occurred at a rate of 2% and at least 2 times placebo rate. Since patients
treated only 1 to 3 headaches in the controlled clinical trials, the opportunity
for discontinuation of therapy in response to an adverse event was limited.
In a long-term, open-label study where patients were allowed to treat multiple migraine attacks for up to 1 year, 15 patients (3.6%) discontinued treatment
due to adverse events.
Table 2 lists adverse events that occurred in 5 placebo-controlled clinical
trials of approximately 1,752 exposures to placebo and AMERGE Tablets in adult
migraine patients. The events cited reflect experience gained under closely
monitored conditions of clinical trials in a highly selected patient population.
In actual clinical practice or in other clinical trials, these frequency estimates
may not apply, as the conditions of use, reporting behavior, and the kinds of
patients treated may differ. Only events that occurred at a frequency of 2%
or more in the group treated with AMERGE Tablets 2.5 mg and were more frequent
in that group than in the placebo group are included in Table 2. From this table,
it appears that many of these adverse events are dose related.
Table 2. Treatment-Emergent Adverse Events Reported by at
Least 2% of Patients in Placebo-Controlled Migraine Trials
| Adverse Event Type |
Placebo
(n = 498) |
AMERGE 1 mg
(n = 627) |
AMERGE 2.5 mg
(n = 627) |
| Atypical sensation |
1% |
2% |
4% |
| Paresthesias (all types) |
< 1% |
1% |
2% |
| Gastrointestinal |
5% |
6% |
7% |
| Nausea |
4% |
4% |
5% |
| Neurological |
3% |
4% |
7% |
| Dizziness |
1% |
1% |
2% |
| Drowsiness |
< 1% |
1% |
2% |
| Malaise/fatigue |
1% |
2% |
2% |
| Pain and pressure sensation |
2% |
2% |
4% |
| Throat/neck symptoms |
1% |
1% |
2% |
One event (vomiting) present in more than 1% of patients receiving AMERGE Tablets
occurred more frequently on placebo than on naratriptan 2.5 mg.
AMERGE Tablets are generally well tolerated. Most adverse reactions were mild
and transient.
The incidence of adverse events in placebo-controlled clinical trials was not
affected by age or weight of the patients, duration of headache prior to treatment,
presence of aura, use of prophylactic medications, or tobacco use. There was
insufficient data to assess the impact of race on the incidence of adverse events.
Other Events Observed in Association With the Administration of AMERGE Tablets:
In the paragraphs that follow, the frequencies of less commonly reported adverse
clinical events are presented. Because the reports include events observed in
open and uncontrolled studies, the role of AMERGE Tablets in their causation
cannot be reliably determined. Furthermore, variability associated with adverse
event reporting, the terminology used to describe adverse events, etc., limit
the value of the quantitative frequency estimates provided. Event frequencies
are calculated as the number of patients reporting an event divided by the total
number of patients (n = 3,557) exposed to oral naratriptan doses up to 10 mg.
All reported events are included except those already listed in the previous
table, those too general to be informative, and those not reasonably associated
with the use of the drug. Events are further classified within body system categories
and enumerated in order of decreasing frequency using the following definitions:
frequent adverse events are those occurring in at least 1/100 patients, infrequent
adverse events are those occurring in 1/100 to 1/1,000 patients, and rare adverse
events are those occurring in fewer than 1/1,000 patients.
Atypical Sensations: Frequent were warm/cold temperature sensations.
Infrequent were feeling strange and burning/stinging sensation.
Cardiovascular: Infrequent were palpitations, increased blood
pressure, tachyarrhythmias, and abnormal ECG (PR prolongation, QTc
prolongation, ST/T wave abnormalities, premature ventricular contractions, atrial
flutter, or atrial fibrillation), and syncope. Rare were bradycardia, varicosities,
hypotension, and heart murmurs.
Ear, Nose, and Throat:Frequent were ear, nose, and thro at infections.
Infrequent were phonophobia, sinusitis, upper respiratory inflammation, and
tinnitus. Rare were allergic rhinitis; labyrinthitis; ear, nose, and throat
hemorrhage; and hearing difficulty.
Endocrine and Metabolic: Infrequent were thirst and polydipsia,
dehydration, and fluid retention. Rare were hyperlipidemia, hypercholesterolemia,
hypothyroidism, hyperglycemia, glycosuria and ketonuria, and parathyroid neoplasm.
Eye: Frequent was photophobia. Infrequent was blurred vision.
Rare were eye pain and discomfort, sensation of eye pressure, eye hemorrhage,
dry eyes, difficulty focusing, and scotoma.
Gastrointestinal: Frequent were hyposalivation and vomiting.
Infrequent were dyspeptic symptoms, diarrhea, gastrointestinal discomfort and
pain, gastroenteritis, and constipation. Rare were abnormal liver function tests,
abnormal bilirubin levels, hemorrhoids, gastritis, esophagitis, salivary gland
inflammation, oral itching and irritation, regurgitation and reflux, and gastric
ulcers.
Hematological Disorders: Infrequent was increased white cells.
Rare were thrombocytopenia, quantitative red cell or hemoglobin defects, anemia,
and purpura.
Lower Respiratory Tract: Infrequent were bronchitis, cough, and
pneumonia. Rare were tracheitis, asthma, pleuritis, and airway constriction
and obstruction.
Musculoskeletal: Infrequent were muscle pain, arthralgia and
articular rheumatism, muscle cramps and spasms, joint and muscle stiffness,
tightness, and rigidity. Rare were bone and skeletal pain.
Neurological: Frequent was vertigo. Infrequent were tremors,
cognitive function disorders, sleep disorders, and disorders of equilibrium.
Rare were compressed nerve syndromes, confusion, sedation, hyperesthesia, coordination
disorders, paralysis of cranial nerves, decreased consciousness, dreams, altered
sense of taste, neuralgia, neuritis, aphasia, hypoesthesia, motor retardation,
muscle twitching and fasciculation, psychomotor restlessness, and convulsions.
Non-Site Specific: Infrequent were chills and/or fever, descriptions
of odor or taste, edema and swelling, allergies, and allergic reactions. Rare
were spasms and mobility disorders.
Pain and Pressure Sensations: Frequent were pressure/tightness/heaviness
sensations.
Psychiatry: Infrequent were anxiety, depressive disorders, and
detachment. Rare were aggression and hostility, agitation, hallucinations, panic,
and hyperactivity.
Reproduction: Rare were lumps of female reproductive tract, breast
inflammation, inflammation of vagina, inflammation of fallopian tube, breast
discharge, endometrium disorders, decreased libido, and lumps of breast.
Skin: Infrequent were sweating, skin rashes, pruritus, and urticaria.
Rare were skin erythema, dermatitis and dermatosis, hair loss and alopecia,
pruritic skin rashes, acne and folliculitis, allergic skin reactions, macular
skin/rashes, skin photosensitivity, photodermatitis, skin flakiness, and dry
skin.
Urology: Infrequent were bladder inflammation and polyuria and
diuresis. Rare were urinary tract hemorrhage, urinary urgency, pyelitis, and
urinary incontinence.
Observed During Clinical Practice: The following section enumerates
potentially important adverse events that have occurred in clinical practice
and that have been reported spontaneously to various surveillance systems. The
events enumerated represent reports arising from both domestic and nondomestic
use of naratriptan. These events do not include those already listed in the
ADVERSE REACTIONS section above. Because the reports cite events reported spontaneously
from worldwide postmarketing experience, frequency of events and the role of
naratriptan in their causation cannot be reliably determined.
Cardiovascular: Angina, myocardial infarction (see WARNINGS).
Gastrointestinal: Colonic ischemia (see WARNINGS).
Lower Respiratory: Dyspnea.
Miscellaneous: Hypersensitivity, including anaphylaxis/anaphylactoid
reactions, in some cases severe (e.g., circulatory collapse) (see WARNINGS).
Neurologic: Cerebral vascular accident, including transient ischemic
attack, subarachnoid hemorrhage, and cerebral infarction (see WARNINGS);
serotonin syndrome.
Drug Abuse And Dependence
In one clinical study enrolling 12 subjects, all of whom had experience using
oral opiates and other psychoactive drugs, AMERGE Tablets produced less intense
subjective responses ordinarily associated with many drugs of abuse than did
codeine (30 to 90 mg).