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Medication Safety Issues
Sound-alike/look-alike issues:
Amerge® may be confused with Altace®, Amaryl®
Pronunciation
(NAR a trip tan)
U.S. Brand Names
Index Terms
Generic Available
No
Canadian Brand Names
Pharmacologic Category
Pharmacologic Category Synonyms
Use: Labeled Indications
Treatment of acute migraine headache with or without aura
Pregnancy Risk Factor
C
Pregnancy Considerations
There are no adequate and well-controlled studies using naratriptan in pregnant women. Use only if potential benefit to the mother outweighs the potential risk to the fetus. A pregnancy registry has been established to monitor outcomes of women exposed to naratriptan during pregnancy (800-336-2176). In animal studies, administration was associated with embryolethality, fetal abnormalities, and pup mortality and growth retardation. Tremors were observed in the offspring of female rats when exposed to naratriptan late in gestation.
Lactation
Excretion in breast milk unknown/use caution
Contraindications
Hypersensitivity to naratriptan or any component of the formulation; cerebrovascular, peripheral vascular disease (ischemic bowel disease), ischemic heart disease (angina pectoris, history of myocardial infarction, or proven silent ischemia); or in patients with symptoms consistent with ischemic heart disease, coronary artery vasospasm, or Prinzmetal's angina; uncontrolled hypertension or patients who have received within 24 hours another 5-HT agonist (sumatriptan, zolmitriptan) or ergotamine-containing product; patients with known risk factors associated with coronary artery disease; patients with severe hepatic or renal disease (Clcr <15 mL/minute); do not administer naratriptan to patients with hemiplegic or basilar migraine
Warnings/Precautions
Concerns related to adverse effects:
• Cardiac events: Coronary artery vasospasm, transient ischemia, myocardial infarction, ventricular tachycardia/fibrillation, cardiac arrest, and death have been reported with 5-HT1 agonist administration. Patients who experience sensations of chest pain/pressure/tightness or symptoms suggestive of angina following dosing should be evaluated for coronary artery disease or Prinzmetal's angina before receiving additional doses.
• Cerebrovascular events: Cerebral/subarachnoid hemorrhage and stroke have been reported with 5-HT1 agonist administration.
• Elevated blood pressure: Significant elevation in blood pressure, including hypertensive crisis, has also been reported on rare occasions in patients with and without a history of hypertension.
• Vasospasm-related events: Peripheral vascular ischemia and colonic ischemia have been reported with 5-HT1 agonist.
Disease-related concerns:
• Coronary artery disease: Should not be given to patients who have risk factors for CAD (eg, hypertension, hypercholesterolemia, smoker, obesity, diabetes, strong family history of CAD, menopause, male >40 years of age) without adequate cardiac evaluation. Patients with suspected CAD should have cardiovascular evaluation to rule out CAD before considering use; if cardiovascular evaluation “is satisfactory”, first dose should be given in the healthcare provider's office. Periodic evaluation of cardiovascular status should be done in all patients.
Concurrent drug therapy issues:
• Serotonin syndrome: Symptoms of agitation, confusion, hallucinations, hyper-reflexia, myoclonus, shivering, and tachycardia may occur with concomitant proserotonergic drugs (ie, SSRIs/SNRIs or triptans) or agents which reduce naratriptan's metabolism. Concurrent use of serotonin precursors (eg, tryptophan) is not recommended.
Special populations:
• Pediatrics: Safety and efficacy have not been established in children <18 years of age.
Other warnings/precautions:
• Appropriate use: Only indicated for treatment of acute migraine; if a patient does not respond to the first dose, the diagnosis of migraine should be reconsidered.
Adverse Reactions
1% to 10%:
Central nervous system: Dizziness, drowsiness, malaise/fatigue
Gastrointestinal: Nausea, vomiting
Neuromuscular & skeletal: Paresthesia
Miscellaneous: Pain or pressure in throat or neck
<1% (Limited to important or life-threatening): Abnormal bilirubin tests, abnormal liver function tests, allergic reaction, bradycardia, convulsions, coronary artery vasospasm, ECG changes (atrial fibrillation, atrial flutter, premature ventricular contractions, PR prolongation, or QTc prolongation), eye hemorrhage, glycosuria, hallucinations, heart murmurs, hypercholesterolemia, hyperglycemia, hyper-/hypotension, hyperlipidemia, hypothyroidism, ketonuria, MI, palpitation, panic, transient myocardial ischemia, ventricular fibrillation, ventricular tachycardia
Drug Interactions
Ergot Derivatives: May enhance the vasoconstricting effect of Serotonin 5-HT1D Receptor Agonists. Serotonin 5-HT1D Receptor Agonists may enhance the vasoconstricting effect of Ergot Derivatives. Risk X: Avoid combination
Serotonin Modulators: May enhance the adverse/toxic effect of other Serotonin Modulators. The development of serotonin syndrome may occur. Risk D: Consider therapy modification
Sibutramine: May enhance the serotonergic effect of Serotonin Modulators. This may cause serotonin syndrome. Risk X: Avoid combination
Mechanism of Action
Selective agonist for serotonin (5-HT1B and 5-HT1D receptors) in cranial arteries; causes vasoconstriction and reduces sterile inflammation associated with antidromic neuronal transmission correlating with relief of migraine
Pharmacodynamics/Kinetics
Onset of action: 30 minutes
Absorption: Well absorbed
Protein binding, plasma: 28% to 31%
Metabolism: Hepatic via CYP
Bioavailability: 70%
Time to peak: 2-3 hours
Excretion: Urine
Dosage
Adults: Oral: 1-2.5 mg at the onset of headache; it is recommended to use the lowest possible dose to minimize adverse effects. If headache returns or does not fully resolve, the dose may be repeated after 4 hours; do not exceed 5 mg in 24 hours.
Elderly: Not recommended for use in the elderly
Dosing in renal impairment:
Clcr 18-39 mL/minute: Initial: 1 mg; do not exceed 2.5 mg in 24 hours
Clcr <15 mL/minute: Do not use
Dosing in hepatic impairment: Contraindicated in patients with severe liver failure; maximum dose: 2.5 mg in 24 hours for patients with mild or moderate liver failure; recommended starting dose: 1 mg
Administration: Oral
Do not crush or chew tablet; swallow whole with water.
Patient Education
Do not take any new medication during therapy unless approved by prescriber. Do not crush or chew tablet; swallow whole with water. This drug is to be used to reduce your migraine, not to prevent or reduce the number of attacks. If headache returns or is not fully resolved, the dose may be repeated after 4 hours. If you have no relief with first dose, do not take a second dose without consulting prescriber. Do not exceed 5 mg in 24 hours. Do not take within 24 hours of any other migraine medication without first consulting prescriber. May cause dizziness, fatigue, or drowsiness (use caution when driving or engaging in tasks that require alertness until response to drug is known); or nausea or vomiting (small, frequent meals, frequent mouth care, chewing gum, or sucking lozenges may help). Report immediately any chest pain, palpitations, or rapid heartbeat; tightness in throat or neck; or rash, itching, or hives. Pregnancy/breast-feeding precautions: Inform prescriber if you are or intend to become pregnant. Breast-feeding is not recommended.
Geriatric Considerations
Naratriptan was not studied in patients >65 years of age. Use in elderly patients is not recommended because of the presence of risk factors associated with adverse effects. These include the presence of coronary artery disease, decreased liver or renal function, and the risk of pronounced blood pressure increases.
Anesthesia and Critical Care Concerns/Other Considerations
Naratriptan should not be used in patients with a history of vasospastic disease, Prinzmetal's angina, or any critical vascular disease.
Cardiovascular Considerations
Coronary vasospasm has been associated with 5-HT1B/1D agonists. These agents are contraindicated in patients with documented ischemic of vasospastic coronary artery disease. Patients with risk factors for CAD may receive these agents, provided a cardiovascular evaluation yields satisfactory evidence that the patient is free of cardiovascular disease. In patients with risk factors for CAD, administration of the initial dose in a medically staffed/equipped facility (ie, physician's office) is recommended. In addition, ECG monitoring after the initial dose should be considered. Patients who acquire risk factors for CAD, or long-term users of agents from this class of medications, should undergo periodic cardiovascular evaluation.
Dental Health: Effects on Dental Treatment
No significant effects or complications reported
Dental Health: Vasoconstrictor/Local Anesthetic Precautions
No information available to require special precautions
Mental Health: Effects on Mental Status
May cause drowsiness, dizziness, or fatigue; may rarely cause panic reactions or hallucinations
Mental Health: Effects on Psychiatric Treatment
SSRIs may cause hyper-reflexia, weakness, or lack of coordination when used with naratriptan; these combinations should be avoided
Nursing: Physical Assessment/Monitoring
Assess for clear diagnosis of migraine and risk factors for CAD prior to beginning therapy. Assess potential for interactions with other pharmacological agents patient may be taking (eg, ergot-containing drugs, SSRIs). Monitor closely, especially after the first dose. Evaluate therapeutic effectiveness and adverse response (eg, drowsiness, nausea/vomiting, paresthesias, hypertension). If no response to first dose, diagnosis of migraine should be re-evaluated. Teach patient proper use, possible side effects/appropriate interventions, and adverse symptoms to report.
Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Tablet: 1 mg, 2.5 mg
Pricing: U.S. (www.drugstore.com)
Tablets (Amerge)
1 mg (9): $262.54
2.5 mg (9): $264.27
References
Boyer EW and Shannon M, “The Serotonin Syndrome,” N Engl J Med, 2005, 352:1112-20.
International Brand Names
Lexi-Comp.com
Last full review/revision August 2009
Content last modified August 2009
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