Naratriptan

Pronunciation

(NAR a trip tan)

U.S. Brand Names

Amerge®

Synonyms

Naratriptan Hydrochloride

Generic Available

No

Canadian Brand Names

Amerge®

Use

Treatment of acute migraine headache with or without aura

Pregnancy Risk Factor

C

Pregnancy Implications

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

Use only if there is a clear diagnosis of migraine. May cause vasospastic reactions resulting in colonic, peripheral, or coronary ischemia. Monitor closely, especially after the first dose. Patients who are at risk of CAD (based on risk factor evaluation) but have had a satisfactory cardiovascular evaluation may receive naratriptan, but extreme caution should be used; administration of the first dose in a setting with medical staff and equipment (ie, in a physician's office) is recommended, and ECG monitoring after the first dose should be considered. Periodically re-evaluate risk factors for CAD in patients receiving long-term intermittent treatment. Blood pressure may increase with the administration of naratriptan. If the patient does not respond to the first dose, re-evaluate the diagnosis of migraine before trying a second dose.

Adverse Reactions

1% to 10%:

Central nervous system: Dizziness, drowsiness, malaise/fatigue

Gastrointestinal: Nausea, vomiting

Neuromuscular & skeletal: Paresthesias

Miscellaneous: Pain or pressure in throat or neck

<1% (Limited to important or life-threatening): Coronary artery vasospasm, transient myocardial ischemia, MI, ventricular tachycardia, ventricular fibrillation, palpitation, hypertension, ECG changes (PR prolongation, QTc prolongation, premature ventricular contractions, atrial flutter, or atrial fibrillation) hypotension, heart murmurs, bradycardia, hyperlipidemia, hypercholesterolemia, hypothyroidism, hyperglycemia, glycosuria, ketonuria, eye hemorrhage, abnormal liver function tests, abnormal bilirubin tests, convulsions, allergic reaction, panic, hallucinations

Drug Interactions

Decreased effect: Smoking increases the clearance of naratriptan

Increased effect/toxicity: Ergot-containing drugs (dihydroergotamine or methysergide) may cause vasospastic reactions when taken with naratriptan. Avoid concomitant use with ergots; separate dose of naratriptan and ergots by at least 24 hours. Oral contraceptives taken with naratriptan reduced the clearance of naratriptan ~30% which may contribute to adverse effects. Selective serotonin reuptake inhibitors (SSRIs) (eg, fluoxetine, fluvoxamine, paroxetine, sertraline) may cause lack of coordination, hyper-reflexia, or weakness and should be avoided when taking naratriptan.

Mechanism of Action

The therapeutic effect for migraine is due to serotonin agonist activity

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

Patient Education

Inform prescriber of all prescriptions, OTC medications, or herbal products you are taking, and any allergies you have. Do not take any new medication during therapy unless approved by prescriber. 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.

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

Dosage Forms

Tablet: 1 mg, 2.5 mg

International Brand Names

Amerge® (CA); Antimigrin® (AT); Colatan® (ES); Naragran® (DK); Naramig® (AR, AT, AU, BE, BG, BR, CH, CL, CO, CR, DE, DO, EC, ES, FI, FR, GB, GT, HN, HR, HU, IL, MX, NL, NO, PA, PT, RO, RU, SE, SG, SI, SV, TH, TR, ZA); Naramig Orifarm® (DK); Naramig Paranova® (DK)