Dosing and uses of Amerge (naratriptan)
Adult dosage forms and strengths
tablet
- 1mg
- 2.5mg
Migraine
1-2.5 mg PO at onset; may repeat once after 4 hours
Not to exceed 5 mg/day
Renal Impairment
Mild-to-moderate: Not to exceed 2.5 mg/day
Severe (<15 mL/min); Do not administer
Pediatric dosage forms and strengths
Safety and efficacy not established
Geriatric dosage forms and strengths
Not recommended
Amerge (naratriptan) adverse (side) effects
1-10%
Dizziness
Drowsiness
Fatigue
Paresthesias
Pain/pressure sensation
Nausea (1-5%)
Throat/neck symptoms
<1%
Myocardial infarction
Coronary artery vasospasm in pts with CAD risk factors
Warnings
Contraindications
Hypersensitivity, including angioedema and anaphylaxis
Severe hepatic or renal impairment
Wolff-Parkinson-White syndrome or arrhythmias associated with other cardiac accessory conduction pathway disorders
Ischemic heart disease (angina pectoris, history of myocardial infarction, or documented silent ischemia) or coronary artery vasospasm, including Prinzmetal’s angina)
History of stroke or TIA, or history of hemiplegic or basilar migraine because such patients are at a higher risk of stroke
Peripheral vascular disease
Ischemic bowel disease
Uncontrolled hypertension
Do not use within 24 hr of another 5-HT1 agonist or ergot derivative
Cautions
Decrease dose with mild-moderate renal impairment
Overuse of acute migraine drugs (eg, ergotamine, triptans, opioids, or combination of these drugs for ≥10 days/month) may lead to exacerbation of headache (medication overuse headache)
Serotonin syndrome: Potentially life-threatening serotonin syndrome may occur, particularly during combined use with SSRIs (eg, fluoxetine, paroxetine, sertraline, fluvoxamine, citalopram, escitalopram) or SNRIs (eg, venlafaxine, duloxetine)
Myocardial infarction, cardiac arrest, transient ischemia, coronary artery vasopasm reported
Significant increase in blood pressure including hypertensive crisis with acute impairment of organ systems reported
Anaphylaxis/anaphylactoid and hypersensitivity reactions, including angioedema reported (see Contraindications)
May cause dizziness, weakness, or drowsiness (infrequent)
Pregnancy and lactation
Pregnancy category: C
Lactation: unknown; use with caution in breastfeeding
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Amerge (naratriptan)
Mechanism of action
Selective 5-HT1 receptor agonist in cranial arteries
Causes vasoconstriction and reduces inflammation associated with antidronic neuronal transmission associated with relief of migraine
Absorption
Bioavailability: 70%
Peak Plasma Time: 3-4 hr
Peak Plasma Concentration: 50-1,000 ng/ml; 50% higher in women
Distribution
Protein Bound: 28-31%
Vd: 170 L
Metabolism
Via hepatic CYP450 enzymes
Elimination
Half-Life: 6 hr
Excretion: Urine 50%
