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|genericName=Naratriptan
|genericName=Naratriptan
|aOrAn=an
|aOrAn=an
|drugClass=[[antimigraine]] and[[5-HT1]] [[serotonin receptor agonist]]  
|drugClass=[[antimigraine]] and[[5-HT1]] [[serotonin receptor agonist]]
|indicationType=treatment
|indicationType=treatment
|indication=[[migraine]] with or without [[aura]] in adults.
|indication=[[migraine]] with or without [[aura]] in adults
|adverseReactions=[[paresthesias]], [[nausea]], [[dizziness]], [[drowsiness]], [[malaise]]/[[fatigue]], and [[throat]]/[[neck]] symptoms
|adverseReactions=[[paresthesias]], [[nausea]], [[dizziness]], [[drowsiness]], [[malaise]]/[[fatigue]], and [[throat]]/[[neck]] symptoms
|blackBoxWarningTitle=<b><span style="color:#FF0000;">TITLE</span></b>
|blackBoxWarningTitle=<b><span style="color:#FF0000;">TITLE</span></b>
|blackBoxWarningBody=<i><span style="color:#FF0000;">Condition Name:</span></i> (Content)
|blackBoxWarningBody=<i><span style="color:#FF0000;">Condition Name:</span></i> (Content)
|fdaLIADAdult=====Dosing Information====
*The recommended dose of Naratriptan is 1 mg or 2.5 mg.
*If the [[migraine]] returns or if the patient has only partial response, the dose may be repeated once after 4 hours, for a maximum dose of 5 mg in a 24-hour period.
*The safety of treating an average of more than 4 migraine attacks in a 30‑day period has not been established.
====Dosage Adjustment in Patients With Renal Impairment====
*Naratriptan is contraindicated in patients with severe renal impairment ([[creatinine clearance]]: <15 mL/min) because of decreased clearance of the drug.
*In patients with mild to moderate [[renal impairment]], the maximum daily dose should not exceed 2.5 mg over a 24‑hour period and a 1-mg starting dose is recommended.
====Dosage Adjustment in Patients With Hepatic Impairment====
*Naratriptan is contraindicated in patients with severe hepatic impairment ([[Child-Pugh]] grade C) because of decreased clearance.
*In patients with mild or moderate [[hepatic impairment]] ([[Child-Pugh]] grade A or B), the maximum daily dose should not exceed 2.5 mg over a 24-hour period and a 1-mg starting dose is recommended.
|offLabelAdultGuideSupport=There is limited information regarding <i>Off-Label Guideline-Supported Use</i> of Naratriptan in adult patients.
|offLabelAdultGuideSupport=There is limited information regarding <i>Off-Label Guideline-Supported Use</i> of Naratriptan in adult patients.
|offLabelAdultNoGuideSupport=There is limited information regarding <i>Off-Label Non–Guideline-Supported Use</i> of Naratriptan in adult patients.
|offLabelAdultNoGuideSupport=There is limited information regarding <i>Off-Label Non–Guideline-Supported Use</i> of Naratriptan in adult patients.
|offLabelPedGuideSupport=There is limited information regarding <i>Off-Label Guideline-Supported Use</i> of Naratriptan in pediatric patients.
|offLabelPedGuideSupport=There is limited information regarding <i>Off-Label Guideline-Supported Use</i> of Naratriptan in pediatric patients.
|offLabelPedNoGuideSupport=There is limited information regarding <i>Off-Label Non–Guideline-Supported Use</i> of Naratriptan in pediatric patients.
|offLabelPedNoGuideSupport=There is limited information regarding <i>Off-Label Non–Guideline-Supported Use</i> of Naratriptan in pediatric patients.
|alcohol=Alcohol-Naratriptan interaction has not been established. Talk to your doctor about the effects of taking alcohol with this medication.
|contraindications='''Naratriptan is contraindicated in patients with:'''
}}
*[[Ischemic coronary artery disease]] ([[CAD]]) ([[angina pectoris]], history of [[myocardial infarction]], or documented [[silent ischemia]]) or coronary artery [[vasospasm]], including [[Prinzmetal’s angina]]
{{Naratriptan}}
*[[Wolff-Parkinson-White syndrome]] or [[arrhythmias]] associated with other cardiac accessory conduction pathway disorders
{{Drugbox
*History of [[stroke]] or [[transient ischemic attack]] ([[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]].
*Recent use (i.e., within 24 hours) of another [[5-HT1]] agonist, [[ergotamine]]-containing medication, ergot-type medication (such as [[dihydroergotamine]] or [[methysergide]])
*[[Hypersensitivity]] to Naratriptan ([[angioedema]] and [[anaphylaxis]] seen)
*Severe [[renal impairment]] or [[hepatic impairment]].
|warnings=====Myocardial Ischemia, Myocardial Infarction, and Prinzmetal’s Angina====
*Naratriptan is contraindicated in patients with ischemic or vasospastic [[CAD]]. There have been rare reports of serious cardiac adverse reactions, including acute [[myocardial infarction]], occurring within a few hours following administration of Naratriptan. Some of these reactions occurred in patients without known [[CAD]]. Naratriptan may cause [[coronary artery vasospasm]] ([[Prinzmetal’s angina]]), even in patients without a history of [[CAD]].
*Perform a cardiovascular evaluation in triptan-naive patients who have multiple cardiovascular risk factors (e.g., increased age, [[diabetes]], [[hypertension]], [[smoking]], [[obesity]], strong family history of [[CAD]]) prior to receiving Naratriptan. If there is evidence of [[CAD]] or coronary [[artery vasospasm]], Naratriptan is contraindicated. For patients with multiple cardiovascular risk factors who have a negative cardiovascular evaluation, consider administering the first dose of Naratriptan in a medically supervised setting and performing an [[electrocardiogram]] ([[ECG]]) immediately following administration of Naratriptan. For such patients, consider periodic cardiovascular evaluation in intermittent long-term users of Naratriptan.
 
====Arrhythmias====
*Life-threatening disturbances of cardiac rhythm, including [[ventricular tachycardia]] and [[ventricular fibrillation]] leading to death, have been reported within a few hours following the administration of [[5-HT1]] agonists. Discontinue Naratriptan if these disturbances occur. Naratriptan is contraindicated in patients with [[Wolff-Parkinson-White syndrome]] or [[arrhythmias]] associated with other cardiac accessory conduction pathway disorders.
 
====Chest, Throat, Neck, and/or Jaw Pain/Tightness/Pressure====
*Sensations of tightness, pain, and pressure in the chest, throat, neck, and jaw commonly occur after treatment with Naratriptan and are usually non-cardiac in origin. However, perform a cardiac evaluation if these patients are at high cardiac risk. [[5-HT1]] agonists, including Naratriptan, are contraindicated in patients with [[CAD]] and those with [[Prinzmetal’s]] variant angina.
 
====Cerebrovascular Events====
*[[Cerebral hemorrhage]], [[subarachnoid hemorrhage]], and [[stroke]] have occurred in patients treated with [[5-HT1]] agonists, and some have resulted in fatalities. In a number of cases, it appears possible that the cerebrovascular events were primary, the [[5-HT1]] agonist having been administered in the incorrect belief that the symptoms experienced were a consequence of migraine when they were not. Also, patients with migraine may be at increased risk of certain cerebrovascular events (e.g., stroke, hemorrhage, TIA). Discontinue Naratriptan if a cerebrovascular event occurs.
*Before treating [[headaches]] in patients not previously diagnosed as migraineurs, and in migraineurs who present with symptoms atypical for [[migraine]], exclude other potentially serious neurological conditions. Naratriptan is contraindicated in patients with a history of [[stroke]] or [[TIA]].
 
====Other Vasospasm Reactions====
*Naratriptan may cause non-coronary vasospastic reactions, such as [[peripheral vascular ischemia]], gastrointestinal vascular ischemia and infarction (presenting with [[abdominal pain]] and [[bloody diarrhea]]), [[splenic infarction]], and [[Raynaud’s syndrome]]. In patients who experience symptoms or signs suggestive of non-coronary vasospasm reaction following the use of any 5-HT1 agonist, rule out a vasospastic reaction before receiving additional doses of Naratriptan.
*Reports of transient and permanent [[blindness]] and significant partial [[vision loss]] have been reported with the use of [[5-HT1]] agonists. Since visual disorders may be part of a [[migraine attack]], a causal relationship between these events and the use of [[5-HT1]] agonists have not been clearly established.
 
====Medication Overuse Headache====
*Overuse of [[acute migraine]] drugs (e.g., [[ergotamine]], [[triptans]], [[opioids]], or combination of these drugs for 10 or more days per month) may lead to exacerbation of [[headache]] (medication overuse headache). Medication overuse headache may present as migraine-like daily headaches or as a marked increase in frequency of [[migraine attacks]]. Detoxification of patients, including withdrawal of the overused drugs, and treatment of withdrawal symptoms (which often includes a transient worsening of headache) may be necessary.
 
====Serotonin Syndrome====
*[[Serotonin syndrome]] may occur with Naratriptan, particularly during co-administration with [[selective serotonin reuptake inhibitors]] ([[SSRIs]]), [[serotonin norepinephrine reuptake inhibitors]] ([[SNRIs]]), [[tricyclic antidepressants]] ([[TCAs]]), and [[monoamine oxidase inhibitors]] ([[MAO]]). [[Serotonin syndrome]] symptoms may include mental status changes (e.g., [[agitation]], [[hallucinations]], [[coma]]), autonomic instability (e.g., [[tachycardia]], labile [[blood pressure]], [[hyperthermia]]), neuromuscular aberrations (e.g., hyperreflexia, incoordination), and/or gastrointestinal symptoms (e.g., nausea, vomiting, diarrhea). The onset of symptoms usually occurs within minutes to hours of receiving a new or a greater dose of a serotonergic medication. Discontinue Naratriptan if serotonin syndrome is suspected.
 
====Increase in Blood Pressure====
*Significant elevation in [[blood pressure]], including [[hypertensive crisis]] with acute impairment of organ systems, has been reported on rare occasions in patients treated with [[5-HT1]] agonists, including patients without a history of [[hypertension]]. Monitor blood pressure in patients treated with Naratriptan. Naratriptan is contraindicated in patients with uncontrolled [[hypertension]].
 
====Anaphylactic/Anaphylactoid Reactions====
*There have been reports of [[anaphylaxis]] and [[anaphylactoid]] and [[hypersensitivity reactions]], including [[angioedema]], in patients receiving Naratriptan. Such reactions can be life threatening or fatal. In general, [[anaphylactic reactions]] to drugs are more likely to occur in individuals with a history of sensitivity to multiple allergens. Naratriptan is contraindicated in patients with a history of [[hypersensitivity]] reaction to Naratriptan.
|clinicalTrials=*[[Myocardial ischemia]], [[myocardial infarction]], and [[Prinzmetal’s angina]].
*[[Arrhythmias]].
*Chest, throat, neck, and/or jaw pain/tightness/pressure.
*[[Cerebrovascular events]].
*Other [[vasospasm reactions]].
*Medication overuse headache.
*[[Serotonin syndrome]].
*Increase in [[blood pressure]].
*Hypersensitivity reactions.
 
<i>Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.</i>
*In a long-term open-label trial where patients were allowed to treat multiple migraine attacks for up to 1 year, 15 patients (3.6%) discontinued treatment due to adverse reactions.
*In controlled clinical trials, the most common adverse reactions were ��[[paresthesias]], [[dizziness]], [[drowsiness]], [[malaise]]/[[fatigue]], and throat/neck symptoms, which occurred at a rate of 2% and at least 2 times placebo rate.
*Table 1 lists the adverse reactions that occurred in 5 placebo-controlled clinical trials of approximately 1,752 exposures to placebo and Naratriptan in adult patients with migraine. Only reactions that occurred at a frequency of 2% or more in groups treated with Naratriptan 2.5 mg and that occurred at a frequency greater than the placebo group in the 5 pooled trials are included in Table 1.
 
[[file:Naratriptan AR!.png|none|300px]]
|drugInteractions=====Ergot-Containing Drugs====
*[[Ergot]]-containing drugs have been reported to cause prolonged [[vasospastic reactions]]. Because these effects may be additive, use of ergotamine-containing or [[ergot]]-type medications (like [[dihydroergotamine]] or [[methysergide]]) and Naratriptan within 24 hours of each other is contraindicated.
 
====Other 5-HT1 Agonists====
*Concomitant use of other [[5-HT1B]]/1D agonists (including [[triptans]]) within 24 hours of treatment with Naratriptan is contraindicated because the risk of [[vasospastic reactions]] may be additive.
 
====Selective Serotonin Reuptake Inhibitors/Serotonin Norepinephrine Reuptake Inhibitors and Serotonin Syndrome====
*Cases of serotonin syndrome have been reported during co-administration of triptans and [[SSRIs]], [[SNRIs]], [[TCAs]], and [[MAO inhibitors]].
|FDAPregCat=C
|useInPregnancyFDA=*There are no adequate and well-controlled trials in pregnant women. Naratriptan should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
*In reproductive toxicity studies in rats and rabbits, oral administration of naratriptan was associated with developmental toxicity (embryolethality, fetal abnormalities, pup mortality, offspring growth retardation) at doses producing maternal plasma drug exposures as low as 11 and 2.5 times, respectively, the exposure in humans receiving the maximum recommended daily dose (MRDD) of 5 mg.
*When naratriptan was administered to pregnant rats during the period of organogenesis at doses of 10, 60, or 340 mg/kg/day, there was a dose-related increase in embryonic death; incidences of fetal structural variations (incomplete/irregular ossification of skull bones, sternebrae, ribs) were increased at all doses. The maternal plasma exposures (AUC) at these doses were approximately 11, 70, and 470 times the exposure in humans at the MRDD. The high dose was maternally toxic, as evidenced by decreased maternal body weight gain during gestation. A no-effect dose for developmental toxicity in rats exposed during organogenesis was not established.
*When naratriptan was administered orally (1, 5, or 30 mg/kg/day) to pregnant Dutch rabbits throughout organogenesis, the incidence of a specific fetal skeletal malformation (fused sternebrae) was increased at the high dose, and increased incidences of embryonic death and fetal variations (major blood vessel variations, supernumerary ribs, incomplete skeletal ossification) were observed at all doses (4, 20, and 120 times, respectively, the MRDD on a body surface area basis). Maternal toxicity (decreased body weight gain) was evident at the high dose in this study. In a similar study in New Zealand White rabbits (1, 5, or 30 mg/kg/day throughout organogenesis), decreased fetal weights and increased incidences of fetal skeletal variations were observed at all doses (maternal exposures equivalent to 2.5, 19, and 140 times exposure in humans receiving the MRDD), while maternal body weight gain was reduced at 5 mg/kg or greater. A no-effect dose for developmental toxicity in rabbits exposed during organogenesis was not established.
*When female rats were treated orally with naratriptan (10, 60, or 340 mg/kg/day) during late gestation and lactation, offspring behavioral impairment (tremors) and decreased offspring viability and growth were observed at doses of 60 mg/kg or greater, while maternal toxicity occurred only at the highest dose. Maternal exposures at the no-effect dose for developmental effects in this study were approximately 11 times the exposure in humans receiving the MRDD.
|useInNursing=*Naratriptan is excreted in rat milk. It is not known whether naratriptan is excreted in human milk. Because many drugs are excreted in human milk, and because of the potential for serious adverse reactions in nursing infants from Naratriptan, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
|useInPed=*Safety and effectiveness in pediatric patients have not been established. Therefore, Naratriptan is not recommended for use in patients younger than 18 years of age.
*One controlled clinical trial evaluated Naratriptan (0.25 to 2.5 mg) in 300 adolescent migraineurs aged 12 to 17 years who received at least 1 dose of Naratriptan for an acute migraine. In this study, 54% of the patients were female and 89% were Caucasian. There were no statistically significant differences between any of the treatment groups. The headache response rates at 4 hours (n) were 65% (n = 74), 67% (n = 78), and 64% (n = 70) for placebo, 1-mg, and 2.5-mg groups, respectively. This trial did not establish the efficacy of Naratriptan compared with placebo in the treatment of migraine in adolescents. Adverse reactions observed in this clinical trial were similar in nature to those reported in clinical trials in adults.
|useInGeri=*Clinical trials of Naratriptan did not include sufficient numbers of patients aged 65 and older to determine whether they respond differently from younger patients. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function and of concomitant disease or other drug therapy.
*Naratriptan is known to be substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in elderly patients who have reduced renal function. In addition, elderly patients are more likely to have decreased hepatic function, they are at higher risk for CAD, and blood pressure increases may be more pronounced in the elderly.
*A cardiovascular evaluation is recommended for geriatric patients who have other cardiovascular risk factors (e.g., [[diabetes]], [[hypertension]], smoking, [[obesity]], strong family history of [[CAD]]) prior to receiving Naratriptan
|useInRenalImpair=*The use of Naratriptan is contraindicated in patients with severe renal impairment (creatinine clearance: <15 mL/min) because of decreased clearance of the drug. In patients with mild to moderate renal impairment, the recommended starting dose is 1 mg, and the maximum daily dose should not exceed 2.5 mg over a 24-hour period.
|useInHepaticImpair=*The use of Naratriptan is contraindicated in patients with severe hepatic impairment ([[Child-Pugh]] grade C) because of decreased clearance. In patients with mild or moderate hepatic impairment ([[Child-Pugh]] grade A or B), the recommendedstarting dose is 1 mg, and the maximum daily dose should not exceed 2.5 mg over a 24-hour period.
|overdose=*Adverse reactions observed after overdoses of up to 25 mg included increases in [[blood pressure]] resulting in [[lightheadedness]], [[neck tension]], [[tiredness]], and [[loss of coordination]]. Also, ischemic ECG changes likely due to [[coronary artery vasospasm]] have been reported.
*The elimination half-life of naratriptan is about 6 hours , and therefore monitoring of patients after overdose with Naratriptan should continue for at least 24 hours or while symptoms or signs persist. There is no specific antidote to naratriptan. It is unknown what effect hemodialysis or peritoneal dialysis has on the serum concentrations of naratriptan.
|drugBox={{Drugbox2
| verifiedrevid = 462258702
| verifiedrevid = 462258702
| IUPAC_name = ''N''-methyl-2-[3-(1-methylpiperidin-4-yl)-1''H''-indol-5-yl]ethanesulfonamide
| IUPAC_name = ''N''-methyl-2-[3-(1-methylpiperidin-4-yl)-1''H''-indol-5-yl]ethanesulfonamide
| image2 = Naratriptan-3d-sticks.png
| image = Naratriptan structure.png
 
<!--Clinical data-->
<!--Clinical data-->
| tradename = Amerge
| tradename = Naratriptan
| Drugs.com = {{drugs.com|monograph|naratriptan-hydrochloride}}
| Drugs.com = {{drugs.com|monograph|naratriptan-hydrochloride}}
| MedlinePlus = a601083
| MedlinePlus = a601083
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| legal_status = Rx-only
| legal_status = Rx-only
| routes_of_administration = [[Mouth|Oral]]
| routes_of_administration = [[Mouth|Oral]]
<!--Pharmacokinetic data-->
<!--Pharmacokinetic data-->
| bioavailability = 74%
| bioavailability = 74%
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| elimination_half-life = 5-8 hours
| elimination_half-life = 5-8 hours
| excretion = [[Kidney|Renal]]
| excretion = [[Kidney|Renal]]
<!--Identifiers-->
<!--Identifiers-->
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo_Ref = {{cascite|correct|CAS}}
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| IUPHAR_ligand = 45
| IUPHAR_ligand = 45
| DrugBank_Ref = {{drugbankcite|correct|drugbank}}
| DrugBank_Ref = {{drugbankcite|correct|drugbank}}
| DrugBank = DB00952
| DrugBank = DB00952
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 4287
| ChemSpiderID = 4287
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| ChEMBL_Ref = {{ebicite|correct|EBI}}
| ChEMBL_Ref = {{ebicite|correct|EBI}}
| ChEMBL = 1278
| ChEMBL = 1278
<!--Chemical data-->
<!--Chemical data-->
| C=17 | H=25 | N=3 | O=2 | S=1  
| C=17 | H=25 | N=3 | O=2 | S=1  
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| StdInChIKey = AMKVXSZCKVJAGH-UHFFFAOYSA-N
| StdInChIKey = AMKVXSZCKVJAGH-UHFFFAOYSA-N
}}
}}
__NOTOC__
|mechAction=*Naratriptan binds with high affinity to human cloned 5-HT1B/1D receptors. Migraines are likely due to local cranial vasodilatation and/or to the release of sensory neuropeptides (including substance P and calcitonin gene-related peptide) through nerve endings in the trigeminal system. The therapeutic activity of Naratriptan for the treatment of migraine headache is thought to be due to the agonist effects at the 5-HT1B/1D receptors on intracranial blood vessels (including the arterio-venous anastomoses) and sensory nerves of the trigeminal system, which result in cranial vessel constriction and inhibition of pro-inflammatory neuropeptide release.
{{CMG}}
|structure=*Naratriptan hydrochloride is chemically designated as N-methyl-3-(1-methyl-4-piperidinyl)-1H-indole-5-ethanesulfonamide monohydrochloride, and it has the following structure:
[[file:Naratriptan structure.png|none|300px]]
|PD=*In the anesthetized dog, naratriptan has been shown to reduce the carotid arterial blood flow with little or no effect on arterial blood pressure or total peripheral resistance. While the effect on blood flow was selective for the carotid arterial bed, increases in vascular resistance of up to 30% were seen in the coronary arterial bed. Naratriptan has also been shown to inhibit trigeminal nerve activity in rat and cat.
*In 10 subjects with suspected CAD undergoing coronary artery catheterization, there was a 1% to 10% reduction in coronary artery diameter following subcutaneous injection of 1.5 mg of naratriptan
|PK=====Absorption====
*Naratriptan is well absorbed, with about 70% oral bioavailability. Following administration of a 2.5-mg tablet, the peak concentrations are obtained in 2 to 3 hours. After administration of 1- or 2.5-mg tablets, the Cmax is somewhat (about 50%) higher in women (not corrected for milligram-per-kilogram dose) than in men. During a migraine attack, absorption is slower, with a Tmax of 3 to 4 hours. Food does not affect the pharmacokinetics of naratriptan. Naratriptan displays linear kinetics over the therapeutic dose range.


'''''For patient information about Naratriptan, click [[Naratriptan (patient information)|here]].'''''
====Distribution====
*The steady-state volume of distribution of naratriptan is 170 L. Plasma protein binding is 28% to 31% over the concentration range of 50 to 1,000 ng/mL.


{{SB}} NARATRIPTAN
====Metabolism====
*In vitro, naratriptan is metabolized by a wide range of cytochrome [[P450 isoenzymes]] into a number of inactive metabolites.


==Overview==
====Elimination====
*Naratriptan is predominantly eliminated in urine, with 50% of the dose recovered unchanged and 30% as metabolites in urine. The mean elimination half-life of naratriptan is 6 hours. The systemic clearance of naratriptan is 6.6 mL/min/kg. The renal clearance (220 mL/min) exceeds glomerular filtration rate, indicating active tubular secretion. Repeat administration of naratriptan tablets does not result in drug accumulation.
|nonClinToxic====Carcinogenesis, Mutagenesis, Impairment of Fertility===
====Carcinogenesis====
*In carcinogenicity studies, mice and rats were given naratriptan by oral gavage for 104 weeks. There was no evidence of an increase in tumors related to naratriptan administration in mice receiving up to 200 mg/kg/day. That dose was associated with a plasma (AUC) exposure that was 110 times the exposure in humans receiving the maximum recommended daily dose (MRDD) of 5 mg. Two rat studies were conducted, one using a standard diet and the other a nitrite-supplemented diet (naratriptan can be nitrosated in vitro to form a mutagenic product that has been detected in the stomachs of rats fed a high-nitrite diet). Doses of 5, 20, and 90 mg/kg were associated with AUC exposures that in the standard-diet study were 7, 40, and 236 times, respectively, and in the nitrite-supplemented diet study were 7, 29, and 180 times, respectively, the exposure in humans at the MRDD. In both studies, there was an increase in the incidence of thyroid follicular hyperplasia in high-dose males and females and in thyroid follicular adenomas in high-dose males. In the standard-diet study only, there was also an increase in the incidence of benign c-cell adenomas in the thyroid of high-dose males and females. The exposures achieved at the no-effect dose for thyroid tumors were 40 (standard diet) and 29 (nitrite-supplemented diet) times the exposure achieved in humans at the MRDD. In the nitrite-supplemented diet study only, the incidence of benign lymphocytic thymoma was increased in all treated groups of females. It was not determined if the nitrosated product is systemically absorbed. However, no changes were seen in the stomachs of rats in that study.


'''Naratriptan''' (trade names include '''Amerge''' and '''Naramig''') is a [[triptan]] [[medication|drug]] marketed by [[GlaxoSmithKline]] and is used for the treatment of [[migraine]] [[headaches]]. Naratriptan is available in 2.5&nbsp;mg tablets. It is a selective [[5-HT1|5-HT<sub>1</sub>]] receptor subtype [[agonist]].
====Mutagenesis====
*Naratriptan was not mutagenic when tested in in vitro gene mutation (Ames and mouse lymphoma tk) assays. Naratriptan was also negative in the in vitro human lymphocyte assay and the in vivo mouse micronucleus assay. Naratriptan can be nitrosated in vitro to form a mutagenic product (WHO nitrosation assay) that has been detected in the stomachs of rats fed a nitrite-supplemented diet.


==Category==
====Impairment of Fertility====
*In a reproductive toxicity study in which male and female rats were administered naratriptan orally prior to and throughout the mating period (10, 60, 170, or 340 mg/kg/day; plasma exposures [AUC] approximately 11, 70, 230, and 470 times, respectively, the human exposure at the MRDD), there was a treatment-related decrease in the number of females exhibiting normal estrous cycles at doses of 170 mg/kg/day or greater and an increase in preimplantation loss at 60 mg/kg/day or greater. In high-dose males, testicular/epididymal atrophy accompanied by spermatozoa depletion reduced mating success and may have contributed to the observed preimplantation loss. The exposures achieved at the no-effect doses for preimplantation loss, anestrus, and testicular effects were approximately 11, 70, and 230 times, respectively, the exposures in humans at the MRDD.
*In a study in which rats were dosed orally with naratriptan (10, 60, or 340 mg/kg/day) for 6 months, changes in the female reproductive tract including atrophic or cystic ovaries and anestrus were seen at the high dose. The exposure at the no-effect dose of 60 mg/kg was approximately 85 times that in humans at the MRDD.
|clinicalStudies=*The efficacy of Naratriptan in the acute treatment of migraine headaches was evaluated in 3 randomized, double-blind, placebo-controlled trials in adult patients (Trials 1, 2, 3). These trials enrolled adult patients who were predominantly female (86%) and Caucasian (96%) with a mean age of 41 years (range: 18 to 65 years). In all studies, patients were instructed to treat at least 1 moderate to severe headache. Headache response, defined as a reduction in headache severity from moderate or severe pain to mild or no pain, was assessed up to 4 hours after dosing. Associated symptoms such as nausea, vomiting, photophobia, and phonophobia were also assessed. Maintenance of response was assessed for up to 24 hours postdose. A second dose of Naratriptan or other rescue medication to treat migraines was allowed 4 to 24 hours after the initial treatment for recurrent headache.
*In all 3 trials, the percentage of patients achieving headache response 4 hours after treatment, the primary outcome measure, was significantly greater among patients receiving Naratriptan compared with those who received placebo. In all trials, response to 2.5 mg was numerically greater than response to 1 mg and in the largest of the 3 trials, there was a statistically significant greater percentage of patients with headache response at 4 hours in the 2.5-mg group compared with the 1-mg group. The results are summarized in Table 2.


Serotonin Receptor Agonists; Antimigraine Agents
[[file:Naratriptan CS1.png|none|400px]]


==FDA Package Insert==
*Four to 24 hours following the initial dose of study treatment, patients were allowed to use additional treatment for pain relief in the form of a second dose of study treatment or other rescue medication. The estimated probability of patients taking a second dose or other rescue medication to treat migraine over the 24 hours following the initial dose of study treatment is summarized in Figure 2.


'''  [[Naratriptan indications and usage|Indications and Usage]]'''
[[file:Naratriptan CS".png|none|300px]]
'''| [[Naratriptan dosage and administration|Dosage and Administration]]'''
|packLabel=[[file:Naratriptan Packaged1.png|none|300px]]
'''| [[Naratriptan dosage forms and strengths|Dosage Forms and Strengths]]'''
[[file:Naratriptan Package2.png|none|300px]]
'''| [[Naratriptan contraindications|Contraindications]]'''
[[file:Naratriptan Appearance.png|none|400px]]
'''| [[Naratriptan warnings and precautions|Warnings and Precautions]]'''
|alcohol=*Alcohol-Naratriptan interaction has not been established. Talk to your doctor about the effects of taking alcohol with this medication.
'''| [[Naratriptan adverse reactions|Adverse Reactions]]'''
|brandNames=*[[Amerge]]
'''| [[Naratriptan drug interactions|Drug Interactions]]'''
}}
'''| [[Naratriptan use in specific populations|Use in Specific Populations]]'''
'''| [[Naratriptan overdosage|Overdosage]]'''
'''| [[Naratriptan description|Description]]'''
'''| [[Naratriptan clinical pharmacology|Clinical Pharmacology]]'''
'''| [[Naratriptan nonclinical toxicology|Nonclinical Toxicology]]'''
'''| [[Naratriptan clinical studies|Clinical Studies]]'''
'''| [[Naratriptan how supplied storage and handling|How Supplied/Storage and Handling]]'''
'''| [[Naratriptan patient counseling information|Patient Counseling Information]]'''
'''| [[Naratriptan labels and packages|Labels and Packages]]'''
 
==Indication==
 
Naratriptan is used for the treatment of the acute migraine attacks and the symptoms of migraine, including severe, throbbing headaches that sometimes are accompanied by nausea and sensitivity to sound or light.<ref name=medline>Medline Plus Drug Information  for [http://www.nlm.nih.gov/medlineplus/druginfo/meds/a601083.html Naratriptan] Accessed 6 August 2009</ref>
 
==Mechanism of action==
 
The causes of migraine are not clearly understood; however, the efficacy of naratriptans and other triptans is believed to be due to their activity as [[Triptans#Mechanism_of_action|5HT (serotonin) agonists]].
 
==Efficacy==
 
A meta-analysis of 53 clinical trials has shown that all triptans are effective for treating migraine at marketed doses and that naratriptan, although less effective than [[sumatriptan]] and [[rizatriptan]] was more effective than placebo in reducing migraine symptoms at two hours<ref name=ferrari>Triptans (serotonin, 5-HT1B/1D agonists) in migraine: detailed results and methods of a meta-analysis of 53 trials. [http://dx.doi.org/10.1016/S0149-2918(00)80068-5 Cephalalgia 2002 Oct;22(8):633-58.]</ref> and efficacy was demonstrated in almost two thirds of subjects after four hours of treatment.<ref name=havanka>Efficacy of naratriptan tablets in the acute treatment of migraine: A dose-ranging study. [http://dx.doi.org/10.1016/S0149-2918(00)80068-5 Clin Ther 2000 Aug;22(8):970-80.]</ref>
 
==Side effects==
 
Side effects include: dizziness, [[lethargy | drowsiness]], [[paresthesia | tingling of the hands or feet]], nausea, [[xerostomia | dry mouth]] and unsteadiness. If these effects persist or worsen, notify your doctor promptly. Side-effects which are unlikely and which should be promptly reported include: chest pain/pressure, throat pain/pressure, unusually fast/slow/irregular pulse, one-sided muscle weakness, vision problems, [[Raynaud's phenomenon | cold/bluish hands or feet]], stomach pain, bloody diarrhea, mental/mood changes, and [[Syncope (medicine)| fainting]]. In the unlikely event you have a serious allergic reaction to this drug, seek immediate medical attention. Symptoms of a [[anaphylaxis | serious allergic reaction]] include: rash, itching, swelling, severe dizziness, trouble breathing (swelling of the throat).
 
The use of naratriptan with [[MAOI]]s and [[serotonergic]] drugs may result in the life threatening [[serotonin syndrome]]. Make sure your doctor/pharmacist is aware of all your current medications (including [[pro re nata | as needed medications]]) before taking this drug. <ref>(( cite web | url = http://www.drugs.com/cdi/naratriptan.html ))</ref>
 
==Exclusivity==
 
In the United States, the [[Food and Drug Administration]] (FDA) approved naratriptan on February 11, 1998.<ref name=accessdata>FDA AccessData entry for [http://www.accessdata.fda.gov/scripts/cder/ob/docs/obdetail.cfm?Appl_No=020763&TABLE1=OB_Rx Naratriptan Hydrochloride], accessed September 8, 2008</ref>  It was covered by {{US patent|4997841|U.S. Patent no. 4997841}}; the FDA lists the patent as expiring on July 7, 2010.<ref name=accessdata/><ref>{{US patent|4997841|U.S. Patent no. 4997841}}, Alexander W. Oxford, ''et al.'', ''Indole Derivatives'', March 5, 1991</ref>
 
In July 2010, in the wake of the patent expiration, several drug manufacturers, including [[Roxane Labs]],<ref>{{cite news |url=http://drugstorenews.com/story.aspx?id=145645 |title=Roxane launches generic Amerge, Arimidex |first=Alaric |last=DeArment |work=Drug Store News |date=2010-07-09 |accessdate=2010-07-23}}</ref> [[Sandoz]]<ref>{{cite news |url=http://drugstorenews.com/story.aspx?id=145817 |title=Sandoz launches generic Amerge |first=Alaric |last=DeArment |work=Drug Store News |date=2010-07-12 |accessdate=2010-07-23}}</ref> and [[Teva Pharmaceuticals]],<ref>{{cite news |url=http://drugstorenews.com/story.aspx?id=146081 |title=Teva launches generic Amerge |first=Alaric |last=DeArment |work=Drug Store News |date=2010-07-14 |accessdate=2010-07-23}}</ref> announced that they were launching generic Naratriptan medications.
 
The drug continues to be covered by European patent 0303507 in Germany, Spain, France and the United Kingdom through March 10, 2012,<ref name=GenericsWeb>{{cite news |url=http://www.genericsweb.com/druginfocus/Naratriptan_press_release |title=Drug In Focus: Naratriptan |first=Dae |last=Oh |work=GenericsWeb |date=June 2010 |accessdate=2010-12-15}}</ref> and by Australian patent 611469 in Australia through June 17, 2013.<ref name=GenericsWeb/>  It had previously been covered by Canadian patent 1210968; but both Sandoz and [[Novopharm]] have offered generic equivalents in Canada since that patent's expiration December 1, 2009.<ref name=GenericsWeb/>
 
==References==
 
{{Reflist|2}}
 
{{Antimigraine preparations}}
[[Category:Drugs]]
[[Category:Piperidines]]
[[Category:Sulfonamides]]
[[Category:Triptans]]

Latest revision as of 18:54, 27 February 2015

Naratriptan
Adult Indications & Dosage
Pediatric Indications & Dosage
Contraindications
Warnings & Precautions
Adverse Reactions
Drug Interactions
Use in Specific Populations
Administration & Monitoring
Overdosage
Pharmacology
Clinical Studies
How Supplied
Images
Patient Counseling Information
Precautions with Alcohol
Brand Names
Look-Alike Names

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Alberto Plate [2]

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Overview

Naratriptan is an antimigraine and5-HT1 serotonin receptor agonist that is FDA approved for the treatment of migraine with or without aura in adults. Common adverse reactions include paresthesias, nausea, dizziness, drowsiness, malaise/fatigue, and throat/neck symptoms.

Adult Indications and Dosage

FDA-Labeled Indications and Dosage (Adult)

Dosing Information

  • The recommended dose of Naratriptan is 1 mg or 2.5 mg.
  • If the migraine returns or if the patient has only partial response, the dose may be repeated once after 4 hours, for a maximum dose of 5 mg in a 24-hour period.
  • The safety of treating an average of more than 4 migraine attacks in a 30‑day period has not been established.

Dosage Adjustment in Patients With Renal Impairment

  • Naratriptan is contraindicated in patients with severe renal impairment (creatinine clearance: <15 mL/min) because of decreased clearance of the drug.
  • In patients with mild to moderate renal impairment, the maximum daily dose should not exceed 2.5 mg over a 24‑hour period and a 1-mg starting dose is recommended.

Dosage Adjustment in Patients With Hepatic Impairment

  • Naratriptan is contraindicated in patients with severe hepatic impairment (Child-Pugh grade C) because of decreased clearance.
  • In patients with mild or moderate hepatic impairment (Child-Pugh grade A or B), the maximum daily dose should not exceed 2.5 mg over a 24-hour period and a 1-mg starting dose is recommended.

Off-Label Use and Dosage (Adult)

Guideline-Supported Use

There is limited information regarding Off-Label Guideline-Supported Use of Naratriptan in adult patients.

Non–Guideline-Supported Use

There is limited information regarding Off-Label Non–Guideline-Supported Use of Naratriptan in adult patients.

Pediatric Indications and Dosage

FDA-Labeled Indications and Dosage (Pediatric)

There is limited information regarding Naratriptan FDA-Labeled Indications and Dosage (Pediatric) in the drug label.

Off-Label Use and Dosage (Pediatric)

Guideline-Supported Use

There is limited information regarding Off-Label Guideline-Supported Use of Naratriptan in pediatric patients.

Non–Guideline-Supported Use

There is limited information regarding Off-Label Non–Guideline-Supported Use of Naratriptan in pediatric patients.

Contraindications

Naratriptan is contraindicated in patients with:

Warnings

Myocardial Ischemia, Myocardial Infarction, and Prinzmetal’s Angina

  • Naratriptan is contraindicated in patients with ischemic or vasospastic CAD. There have been rare reports of serious cardiac adverse reactions, including acute myocardial infarction, occurring within a few hours following administration of Naratriptan. Some of these reactions occurred in patients without known CAD. Naratriptan may cause coronary artery vasospasm (Prinzmetal’s angina), even in patients without a history of CAD.
  • Perform a cardiovascular evaluation in triptan-naive patients who have multiple cardiovascular risk factors (e.g., increased age, diabetes, hypertension, smoking, obesity, strong family history of CAD) prior to receiving Naratriptan. If there is evidence of CAD or coronary artery vasospasm, Naratriptan is contraindicated. For patients with multiple cardiovascular risk factors who have a negative cardiovascular evaluation, consider administering the first dose of Naratriptan in a medically supervised setting and performing an electrocardiogram (ECG) immediately following administration of Naratriptan. For such patients, consider periodic cardiovascular evaluation in intermittent long-term users of Naratriptan.

Arrhythmias

Chest, Throat, Neck, and/or Jaw Pain/Tightness/Pressure

  • Sensations of tightness, pain, and pressure in the chest, throat, neck, and jaw commonly occur after treatment with Naratriptan and are usually non-cardiac in origin. However, perform a cardiac evaluation if these patients are at high cardiac risk. 5-HT1 agonists, including Naratriptan, are contraindicated in patients with CAD and those with Prinzmetal’s variant angina.

Cerebrovascular Events

  • Cerebral hemorrhage, subarachnoid hemorrhage, and stroke have occurred in patients treated with 5-HT1 agonists, and some have resulted in fatalities. In a number of cases, it appears possible that the cerebrovascular events were primary, the 5-HT1 agonist having been administered in the incorrect belief that the symptoms experienced were a consequence of migraine when they were not. Also, patients with migraine may be at increased risk of certain cerebrovascular events (e.g., stroke, hemorrhage, TIA). Discontinue Naratriptan if a cerebrovascular event occurs.
  • Before treating headaches in patients not previously diagnosed as migraineurs, and in migraineurs who present with symptoms atypical for migraine, exclude other potentially serious neurological conditions. Naratriptan is contraindicated in patients with a history of stroke or TIA.

Other Vasospasm Reactions

  • Naratriptan may cause non-coronary vasospastic reactions, such as peripheral vascular ischemia, gastrointestinal vascular ischemia and infarction (presenting with abdominal pain and bloody diarrhea), splenic infarction, and Raynaud’s syndrome. In patients who experience symptoms or signs suggestive of non-coronary vasospasm reaction following the use of any 5-HT1 agonist, rule out a vasospastic reaction before receiving additional doses of Naratriptan.
  • Reports of transient and permanent blindness and significant partial vision loss have been reported with the use of 5-HT1 agonists. Since visual disorders may be part of a migraine attack, a causal relationship between these events and the use of 5-HT1 agonists have not been clearly established.

Medication Overuse Headache

  • Overuse of acute migraine drugs (e.g., ergotamine, triptans, opioids, or combination of these drugs for 10 or more days per month) may lead to exacerbation of headache (medication overuse headache). Medication overuse headache may present as migraine-like daily headaches or as a marked increase in frequency of migraine attacks. Detoxification of patients, including withdrawal of the overused drugs, and treatment of withdrawal symptoms (which often includes a transient worsening of headache) may be necessary.

Serotonin Syndrome

Increase in Blood Pressure

  • Significant elevation in blood pressure, including hypertensive crisis with acute impairment of organ systems, has been reported on rare occasions in patients treated with 5-HT1 agonists, including patients without a history of hypertension. Monitor blood pressure in patients treated with Naratriptan. Naratriptan is contraindicated in patients with uncontrolled hypertension.

Anaphylactic/Anaphylactoid Reactions

Adverse Reactions

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

  • In a long-term open-label trial where patients were allowed to treat multiple migraine attacks for up to 1 year, 15 patients (3.6%) discontinued treatment due to adverse reactions.
  • In controlled clinical trials, the most common adverse reactions were ��paresthesias, dizziness, drowsiness, malaise/fatigue, and throat/neck symptoms, which occurred at a rate of 2% and at least 2 times placebo rate.
  • Table 1 lists the adverse reactions that occurred in 5 placebo-controlled clinical trials of approximately 1,752 exposures to placebo and Naratriptan in adult patients with migraine. Only reactions that occurred at a frequency of 2% or more in groups treated with Naratriptan 2.5 mg and that occurred at a frequency greater than the placebo group in the 5 pooled trials are included in Table 1.

Postmarketing Experience

There is limited information regarding Naratriptan Postmarketing Experience in the drug label.

Drug Interactions

Ergot-Containing Drugs

Other 5-HT1 Agonists

  • Concomitant use of other 5-HT1B/1D agonists (including triptans) within 24 hours of treatment with Naratriptan is contraindicated because the risk of vasospastic reactions may be additive.

Selective Serotonin Reuptake Inhibitors/Serotonin Norepinephrine Reuptake Inhibitors and Serotonin Syndrome

Use in Specific Populations

Pregnancy

Pregnancy Category (FDA): C

  • There are no adequate and well-controlled trials in pregnant women. Naratriptan should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
  • In reproductive toxicity studies in rats and rabbits, oral administration of naratriptan was associated with developmental toxicity (embryolethality, fetal abnormalities, pup mortality, offspring growth retardation) at doses producing maternal plasma drug exposures as low as 11 and 2.5 times, respectively, the exposure in humans receiving the maximum recommended daily dose (MRDD) of 5 mg.
  • When naratriptan was administered to pregnant rats during the period of organogenesis at doses of 10, 60, or 340 mg/kg/day, there was a dose-related increase in embryonic death; incidences of fetal structural variations (incomplete/irregular ossification of skull bones, sternebrae, ribs) were increased at all doses. The maternal plasma exposures (AUC) at these doses were approximately 11, 70, and 470 times the exposure in humans at the MRDD. The high dose was maternally toxic, as evidenced by decreased maternal body weight gain during gestation. A no-effect dose for developmental toxicity in rats exposed during organogenesis was not established.
  • When naratriptan was administered orally (1, 5, or 30 mg/kg/day) to pregnant Dutch rabbits throughout organogenesis, the incidence of a specific fetal skeletal malformation (fused sternebrae) was increased at the high dose, and increased incidences of embryonic death and fetal variations (major blood vessel variations, supernumerary ribs, incomplete skeletal ossification) were observed at all doses (4, 20, and 120 times, respectively, the MRDD on a body surface area basis). Maternal toxicity (decreased body weight gain) was evident at the high dose in this study. In a similar study in New Zealand White rabbits (1, 5, or 30 mg/kg/day throughout organogenesis), decreased fetal weights and increased incidences of fetal skeletal variations were observed at all doses (maternal exposures equivalent to 2.5, 19, and 140 times exposure in humans receiving the MRDD), while maternal body weight gain was reduced at 5 mg/kg or greater. A no-effect dose for developmental toxicity in rabbits exposed during organogenesis was not established.
  • When female rats were treated orally with naratriptan (10, 60, or 340 mg/kg/day) during late gestation and lactation, offspring behavioral impairment (tremors) and decreased offspring viability and growth were observed at doses of 60 mg/kg or greater, while maternal toxicity occurred only at the highest dose. Maternal exposures at the no-effect dose for developmental effects in this study were approximately 11 times the exposure in humans receiving the MRDD.


Pregnancy Category (AUS): There is no Australian Drug Evaluation Committee (ADEC) guidance on usage of Naratriptan in women who are pregnant.

Labor and Delivery

There is no FDA guidance on use of Naratriptan during labor and delivery.

Nursing Mothers

  • Naratriptan is excreted in rat milk. It is not known whether naratriptan is excreted in human milk. Because many drugs are excreted in human milk, and because of the potential for serious adverse reactions in nursing infants from Naratriptan, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.

Pediatric Use

  • Safety and effectiveness in pediatric patients have not been established. Therefore, Naratriptan is not recommended for use in patients younger than 18 years of age.
  • One controlled clinical trial evaluated Naratriptan (0.25 to 2.5 mg) in 300 adolescent migraineurs aged 12 to 17 years who received at least 1 dose of Naratriptan for an acute migraine. In this study, 54% of the patients were female and 89% were Caucasian. There were no statistically significant differences between any of the treatment groups. The headache response rates at 4 hours (n) were 65% (n = 74), 67% (n = 78), and 64% (n = 70) for placebo, 1-mg, and 2.5-mg groups, respectively. This trial did not establish the efficacy of Naratriptan compared with placebo in the treatment of migraine in adolescents. Adverse reactions observed in this clinical trial were similar in nature to those reported in clinical trials in adults.

Geriatic Use

  • Clinical trials of Naratriptan did not include sufficient numbers of patients aged 65 and older to determine whether they respond differently from younger patients. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function and of concomitant disease or other drug therapy.
  • Naratriptan is known to be substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in elderly patients who have reduced renal function. In addition, elderly patients are more likely to have decreased hepatic function, they are at higher risk for CAD, and blood pressure increases may be more pronounced in the elderly.
  • A cardiovascular evaluation is recommended for geriatric patients who have other cardiovascular risk factors (e.g., diabetes, hypertension, smoking, obesity, strong family history of CAD) prior to receiving Naratriptan

Gender

There is no FDA guidance on the use of Naratriptan with respect to specific gender populations.

Race

There is no FDA guidance on the use of Naratriptan with respect to specific racial populations.

Renal Impairment

  • The use of Naratriptan is contraindicated in patients with severe renal impairment (creatinine clearance: <15 mL/min) because of decreased clearance of the drug. In patients with mild to moderate renal impairment, the recommended starting dose is 1 mg, and the maximum daily dose should not exceed 2.5 mg over a 24-hour period.

Hepatic Impairment

  • The use of Naratriptan is contraindicated in patients with severe hepatic impairment (Child-Pugh grade C) because of decreased clearance. In patients with mild or moderate hepatic impairment (Child-Pugh grade A or B), the recommendedstarting dose is 1 mg, and the maximum daily dose should not exceed 2.5 mg over a 24-hour period.

Females of Reproductive Potential and Males

There is no FDA guidance on the use of Naratriptan in women of reproductive potentials and males.

Immunocompromised Patients

There is no FDA guidance one the use of Naratriptan in patients who are immunocompromised.

Administration and Monitoring

Administration

There is limited information regarding Naratriptan Administration in the drug label.

Monitoring

There is limited information regarding Naratriptan Monitoring in the drug label.

IV Compatibility

There is limited information regarding the compatibility of Naratriptan and IV administrations.

Overdosage

  • Adverse reactions observed after overdoses of up to 25 mg included increases in blood pressure resulting in lightheadedness, neck tension, tiredness, and loss of coordination. Also, ischemic ECG changes likely due to coronary artery vasospasm have been reported.
  • The elimination half-life of naratriptan is about 6 hours , and therefore monitoring of patients after overdose with Naratriptan should continue for at least 24 hours or while symptoms or signs persist. There is no specific antidote to naratriptan. It is unknown what effect hemodialysis or peritoneal dialysis has on the serum concentrations of naratriptan.

Pharmacology

Template:Px
Naratriptan
Systematic (IUPAC) name
N-methyl-2-[3-(1-methylpiperidin-4-yl)-1H-indol-5-yl]ethanesulfonamide
Identifiers
CAS number 121679-13-8
ATC code N02CC02
PubChem 4440
DrugBank DB00952
Chemical data
Formula Template:OrganicBox atomTemplate:OrganicBox atomTemplate:OrganicBoxTemplate:OrganicBoxTemplate:OrganicBoxTemplate:OrganicBoxTemplate:OrganicBoxTemplate:OrganicBoxTemplate:OrganicBoxTemplate:OrganicBoxTemplate:OrganicBoxTemplate:OrganicBoxTemplate:OrganicBoxTemplate:OrganicBox atomTemplate:OrganicBoxTemplate:OrganicBox atomTemplate:OrganicBoxTemplate:OrganicBoxTemplate:OrganicBox atomTemplate:OrganicBoxTemplate:OrganicBoxTemplate:OrganicBoxTemplate:OrganicBox 
Mol. mass 335.465 g/mol
SMILES eMolecules & PubChem
Pharmacokinetic data
Bioavailability 74%
Metabolism Hepatic
Half life 5-8 hours
Excretion Renal
Therapeutic considerations
Pregnancy cat.

B3(AU) C(US)

Legal status

Template:Unicode Prescription only

Routes Oral

Mechanism of Action

  • Naratriptan binds with high affinity to human cloned 5-HT1B/1D receptors. Migraines are likely due to local cranial vasodilatation and/or to the release of sensory neuropeptides (including substance P and calcitonin gene-related peptide) through nerve endings in the trigeminal system. The therapeutic activity of Naratriptan for the treatment of migraine headache is thought to be due to the agonist effects at the 5-HT1B/1D receptors on intracranial blood vessels (including the arterio-venous anastomoses) and sensory nerves of the trigeminal system, which result in cranial vessel constriction and inhibition of pro-inflammatory neuropeptide release.

Structure

  • Naratriptan hydrochloride is chemically designated as N-methyl-3-(1-methyl-4-piperidinyl)-1H-indole-5-ethanesulfonamide monohydrochloride, and it has the following structure:

Pharmacodynamics

  • In the anesthetized dog, naratriptan has been shown to reduce the carotid arterial blood flow with little or no effect on arterial blood pressure or total peripheral resistance. While the effect on blood flow was selective for the carotid arterial bed, increases in vascular resistance of up to 30% were seen in the coronary arterial bed. Naratriptan has also been shown to inhibit trigeminal nerve activity in rat and cat.
  • In 10 subjects with suspected CAD undergoing coronary artery catheterization, there was a 1% to 10% reduction in coronary artery diameter following subcutaneous injection of 1.5 mg of naratriptan

Pharmacokinetics

Absorption

  • Naratriptan is well absorbed, with about 70% oral bioavailability. Following administration of a 2.5-mg tablet, the peak concentrations are obtained in 2 to 3 hours. After administration of 1- or 2.5-mg tablets, the Cmax is somewhat (about 50%) higher in women (not corrected for milligram-per-kilogram dose) than in men. During a migraine attack, absorption is slower, with a Tmax of 3 to 4 hours. Food does not affect the pharmacokinetics of naratriptan. Naratriptan displays linear kinetics over the therapeutic dose range.

Distribution

  • The steady-state volume of distribution of naratriptan is 170 L. Plasma protein binding is 28% to 31% over the concentration range of 50 to 1,000 ng/mL.

Metabolism

  • In vitro, naratriptan is metabolized by a wide range of cytochrome P450 isoenzymes into a number of inactive metabolites.

Elimination

  • Naratriptan is predominantly eliminated in urine, with 50% of the dose recovered unchanged and 30% as metabolites in urine. The mean elimination half-life of naratriptan is 6 hours. The systemic clearance of naratriptan is 6.6 mL/min/kg. The renal clearance (220 mL/min) exceeds glomerular filtration rate, indicating active tubular secretion. Repeat administration of naratriptan tablets does not result in drug accumulation.

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenesis

  • In carcinogenicity studies, mice and rats were given naratriptan by oral gavage for 104 weeks. There was no evidence of an increase in tumors related to naratriptan administration in mice receiving up to 200 mg/kg/day. That dose was associated with a plasma (AUC) exposure that was 110 times the exposure in humans receiving the maximum recommended daily dose (MRDD) of 5 mg. Two rat studies were conducted, one using a standard diet and the other a nitrite-supplemented diet (naratriptan can be nitrosated in vitro to form a mutagenic product that has been detected in the stomachs of rats fed a high-nitrite diet). Doses of 5, 20, and 90 mg/kg were associated with AUC exposures that in the standard-diet study were 7, 40, and 236 times, respectively, and in the nitrite-supplemented diet study were 7, 29, and 180 times, respectively, the exposure in humans at the MRDD. In both studies, there was an increase in the incidence of thyroid follicular hyperplasia in high-dose males and females and in thyroid follicular adenomas in high-dose males. In the standard-diet study only, there was also an increase in the incidence of benign c-cell adenomas in the thyroid of high-dose males and females. The exposures achieved at the no-effect dose for thyroid tumors were 40 (standard diet) and 29 (nitrite-supplemented diet) times the exposure achieved in humans at the MRDD. In the nitrite-supplemented diet study only, the incidence of benign lymphocytic thymoma was increased in all treated groups of females. It was not determined if the nitrosated product is systemically absorbed. However, no changes were seen in the stomachs of rats in that study.

Mutagenesis

  • Naratriptan was not mutagenic when tested in in vitro gene mutation (Ames and mouse lymphoma tk) assays. Naratriptan was also negative in the in vitro human lymphocyte assay and the in vivo mouse micronucleus assay. Naratriptan can be nitrosated in vitro to form a mutagenic product (WHO nitrosation assay) that has been detected in the stomachs of rats fed a nitrite-supplemented diet.

Impairment of Fertility

  • In a reproductive toxicity study in which male and female rats were administered naratriptan orally prior to and throughout the mating period (10, 60, 170, or 340 mg/kg/day; plasma exposures [AUC] approximately 11, 70, 230, and 470 times, respectively, the human exposure at the MRDD), there was a treatment-related decrease in the number of females exhibiting normal estrous cycles at doses of 170 mg/kg/day or greater and an increase in preimplantation loss at 60 mg/kg/day or greater. In high-dose males, testicular/epididymal atrophy accompanied by spermatozoa depletion reduced mating success and may have contributed to the observed preimplantation loss. The exposures achieved at the no-effect doses for preimplantation loss, anestrus, and testicular effects were approximately 11, 70, and 230 times, respectively, the exposures in humans at the MRDD.
  • In a study in which rats were dosed orally with naratriptan (10, 60, or 340 mg/kg/day) for 6 months, changes in the female reproductive tract including atrophic or cystic ovaries and anestrus were seen at the high dose. The exposure at the no-effect dose of 60 mg/kg was approximately 85 times that in humans at the MRDD.

Clinical Studies

  • The efficacy of Naratriptan in the acute treatment of migraine headaches was evaluated in 3 randomized, double-blind, placebo-controlled trials in adult patients (Trials 1, 2, 3). These trials enrolled adult patients who were predominantly female (86%) and Caucasian (96%) with a mean age of 41 years (range: 18 to 65 years). In all studies, patients were instructed to treat at least 1 moderate to severe headache. Headache response, defined as a reduction in headache severity from moderate or severe pain to mild or no pain, was assessed up to 4 hours after dosing. Associated symptoms such as nausea, vomiting, photophobia, and phonophobia were also assessed. Maintenance of response was assessed for up to 24 hours postdose. A second dose of Naratriptan or other rescue medication to treat migraines was allowed 4 to 24 hours after the initial treatment for recurrent headache.
  • In all 3 trials, the percentage of patients achieving headache response 4 hours after treatment, the primary outcome measure, was significantly greater among patients receiving Naratriptan compared with those who received placebo. In all trials, response to 2.5 mg was numerically greater than response to 1 mg and in the largest of the 3 trials, there was a statistically significant greater percentage of patients with headache response at 4 hours in the 2.5-mg group compared with the 1-mg group. The results are summarized in Table 2.
  • Four to 24 hours following the initial dose of study treatment, patients were allowed to use additional treatment for pain relief in the form of a second dose of study treatment or other rescue medication. The estimated probability of patients taking a second dose or other rescue medication to treat migraine over the 24 hours following the initial dose of study treatment is summarized in Figure 2.

How Supplied

There is limited information regarding Naratriptan How Supplied in the drug label.

Storage

There is limited information regarding Naratriptan Storage in the drug label.

Images

Drug Images

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Package and Label Display Panel

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Patient Counseling Information

There is limited information regarding Naratriptan Patient Counseling Information in the drug label.

Precautions with Alcohol

  • Alcohol-Naratriptan interaction has not been established. Talk to your doctor about the effects of taking alcohol with this medication.

Brand Names

Look-Alike Drug Names

There is limited information regarding Naratriptan Look-Alike Drug Names in the drug label.

Drug Shortage Status

Price

References

The contents of this FDA label are provided by the National Library of Medicine.