will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.larotrectinibMinor (1)larotrectinib will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.lenacapavirMonitor Closely (1)lenacapavir will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Lencapavir may increase CYP3A4 substrates initiated within 9 months after last SC dose of lenacapavir, which may increase potential risk of adverse reactions of CYP3A4 substrates.letermovirMonitor Closely (1)letermovir increases levels of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.levoketoconazoleMonitor Closely (1)levoketoconazole will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.lumacaftor/ivacaftorMonitor Closely (2)lumacaftor/ivacaftor, montelukast. affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. In vitro studies suggest that lumacaftor may induce and ivacaftor may inhibit CYP2C9 substrates. . lumacaftor/ivacaftor decreases levels of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. No dose adjustment for montelukast is recommended.lumefantrineMinor (1)lumefantrine will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.marijuanaMinor (1)marijuana will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.methylprednisoloneMinor (1)methylprednisolone will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.metronidazoleMinor (1)metronidazole will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.miconazole vaginalMinor (1)miconazole vaginal will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.mitotaneMonitor Closely (1)mitotane decreases levels of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Mitotane is a strong inducer of cytochrome P-4503A4; monitor when coadministered with CYP3A4 substrates for possible dosage adjustments.nefazodoneMonitor Closely (1)nefazodone will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.nelfinavirMinor (1)nelfinavir will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.nevirapineMinor (1)nevirapine will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.nifedipineMinor (1)nifedipine will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.nilotinibMinor (1)nilotinib will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.nitisinoneMonitor Closely (1)nitisinone will increase the level or effect of montelukast by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. Nitisinone inhibits CYP2C9. Caution if CYP2C9 substrate coadministered, particularly those with a narrow therapeutic index.oxcarbazepineMinor (1)oxcarbazepine will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.peginterferon alfa 2bMonitor Closely (1)peginterferon alfa 2b decreases levels of montelukast by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. When patients are administered peginterferon alpha-2b with CYP2C9 substrates, the therapeutic effect of these drugs may be altered. .pentobarbitalMinor (1)pentobarbital will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.phenobarbitalMinor (1)phenobarbital will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.phenytoinMinor (1)phenytoin will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.posaconazoleMinor (1)posaconazole will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.prednisoneMinor (1)prednisone will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.primidoneMinor (1)primidone will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.quinupristin/dalfopristinMinor (1)quinupristin/dalfopristin will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ribociclibMinor (1)ribociclib will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.rifabutinMonitor Closely (1)rifabutin will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.rifampinMonitor Closely (1)rifampin will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.rifapentineMinor (1)rifapentine will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ritonavirMinor (1)ritonavir will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.rufinamideMinor (1)rufinamide will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.secobarbitalMinor (1)secobarbital will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.sparsentanMonitor Closely (1)sparsentan will decrease the level or effect of montelukast by affecting hepatic enzyme CYP2C9/10 metabolism. Use Caution/Monitor. Sparsentan (a CYP2C9 inducer) decreases exposure of CYP2C9 substrates and reduces efficacy related to these substrates. St John's WortMonitor Closely (1)St John's Wort will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.stiripentolMonitor Closely (1)stiripentol, montelukast. affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Stiripentol is a CYP3A4 inhibitor and inducer. Monitor CYP3A4 substrates coadministered with stiripentol for increased or decreased effects. CYP3A4 substrates may require dosage adjustment.tazemetostatMonitor Closely (1)tazemetostat will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.tecovirimatMonitor Closely (1)tecovirimat will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Tecovirimat is a weak CYP3A4 inducer. Monitor sensitive CYP3A4 substrates for effectiveness if coadministered.topiramateMinor (1)topiramate will decrease the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.tucatinibSerious - Use Alternative (1)tucatinib will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Avoid concomitant use of tucatinib with CYP3A substrates, where minimal concentration changes may lead to serious or life-threatening toxicities. If unavoidable, reduce CYP3A substrate dose according to product labeling.verapamilMinor (1)verapamil will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.voriconazoleMinor (1)voriconazole will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.voxelotorSerious - Use Alternative (1)voxelotor will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Avoid or Use Alternate Drug. Voxelotor increases systemic exposure of sensitive CYP3A4 substrates. Avoid coadministration with sensitive CYP3A4 substrates with a narrow therapeutic index. Consider dose reduction of the sensitive CYP3A4 substrate(s) if unable to avoid.zafirlukastMinor (1)zafirlukast will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. Some adverse drug reactions vary by age group >10% Headache (18.4%; similar to placebo) 1-10% Abdominal pain (≥2%) Eczema (≥2%) Influenza (≥2%) Laryngitis (≥2%) Pharyngitis (≥2%) Viral infection (≥2%) Wheezing (≥2%) Dental pain (2%) Dizziness (2%) Dyspepsia (2%) Elevated liver function tests (2%) Fever (2%) Gastroenteritis (2%) Nasal congestion (2%) Otitis (2%) Rash (2%) Urticaria (2%) Bronchitis (≥1%) Cough (≥1%) Sinusitis (≥1%) Upper respiratory tract infection (≥1%) <1% Allergic granulomatous angiitis (Churg-Strauss syndrome; rare) Cholestatic hepatitis (rare) Aggressive behavior, altered behavior, suicidal thoughts Postmarketing Reports Hematologic: Increased bleeding tendency, thrombocytopenia Immunologic: Hypersensitivity reactions (eg, anaphylaxis, hepatic eosinophilic infiltration) Psychiatric: Agitation, including aggressive behavior or hostility, anxiousness, depression, disorientation, dream abnormalities, hallucinations, insomnia, tic, irritability, restlessness, somnambulism, suicidal thinking and behavior (including suicide), tremor, obsessive compulsive disorders Neurologic: Drowsiness, paresthesia or hypesthesia, seizures, dysphemia (stuttering) Cardiac: Palpitations Respiratory, thoracic, mediastinal: Epistaxis, pulmonary eosinophilia Gastrointestinal: Diarrhea, dyspepsia, nausea, pancreatitis, vomiting Hepatobiliary: Cases of cholestatic hepatitis, hepatocellular liver injury, and mixed-pattern liver injury have been reported, mostly occurring in combination with other confounding factors (eg, use of other medications, administration to patients who had underlying potential for liver disease [eg, alcohol use or other forms of hepatitis]) Dermatologic: Angioedema, bruising, erythema multiforme, erythema nodosum, pruritus, urticaria Musculoskeletal: Arthralgia, myalgia (including muscle cramps) General: Edema Black Box Warnings FDA announcement March 4, 2020 Serious neuropsychiatric events that may include suicidal thoughts or actions have been reported in patients taking montelukast Only use montelukast for allergic rhinitis in patients who have an inadequate response or intolerance to alternative therapies Consider risks and benefits when prescribing or continuing treatment Advise all patients of the risk of neuropsychiatric events when prescribing Discontinue and contact a health care professional immediately if changes in behavior or new neuropsychiatric symptoms, suicidal thoughts, or behavior occur Monitor for neuropsychiatric symptoms Events have occurred in patients with and without pre-existing psychiatric disease Contraindications Hypersensitivity Cautions Not to be given for acute asthma attacks, including status asthmaticus Advise patients to have appropriate rescue medication available Inhaled corticosteroid may be reduced gradually; do not abruptly substitute montelukast for inhaled or oral corticosteroids Patients with known aspirin sensitivity should continue to avoid aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) while taking montelukast; not to be given for treatment of bronchoconstriction resulting from aspirin or NSAID intake Neuropsychiatric events reported, including agitation, aggressive behavior or hostility, anxiousness, depression, disorientation, disturbance in attention, dream abnormalities, hallucinations, insomnia, irritability, memory impairment, restlessness, somnambulism, suicidal thinking and behavior (including suicide), tic, and tremor; prescribers should carefully evaluate the risks and benefits of continuing treatment if such events occur Systemic eosinophilia reported, sometimes presenting with clinical features of vasculitis consistent with Churg-Strauss syndrome; these events are usually (but not always) associated with tapering of PO corticosteroid therapy Use with caution in phenylketonuria; 4-mg and 5-mg chewable tablets contain phenylalanine; before prescribing to a patient with PKU, consider combined daily amount of phenylalanine from all sources, including amount in drug Pregnancy Available data from published prospective and retrospective cohort studies over decades in pregnant women have not established a drug-associated risk of major birth defects Animal data In animal reproduction studies, no adverse developmental effects were observed with oral administration to pregnant rats and rabbits during organogenesis at doses approximately 100 and 110 times, respectively, the maximum recommended human daily oral dose (MRHDOD) based on AUCs Poorly or moderately controlled asthma in pregnancy increases maternal risk of perinatal adverse outcomes such as preeclampsia and infant prematurity, low birth weight, and small for gestational age Lactation A published clinical lactation study reports presence of montelukast in human milk; data available on effects of drug on infants, either directly or through breast milk, do not suggest a significant risk of adverse events from exposure; effects of drug on milk production are unknown; developmental and health benefits of breastfeeding should be considered along with mother’s clinical need for therapy and any potential adverse effects on breastfed infant from treatment or from underlying maternal conditionPregnancy 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. Mechanism of Action Blocks binding of leukotriene D4 to its receptor; alters pathophysiology associated with inflammatory process that contributes to signs and symptoms of asthma Absorption Bioavailability: 64% (mean) Peak plasma time: Tablet, 3-4 hr; chewable tablet, 2-2.5 hr; granules, 1-3 hr Distribution Protein bound: >99% Vd: 8-11 L Metabolism Metabolized by CYP3A4 and CYP2C9 Elimination Half-life: 2.7-5.5 hr Clearance: 45 mL/min Excretion: Feces (86%), urine (0.2%) Oral Administration Take with or without food Patients with both asthma and allergic rhinitis should take only 1 dose qPM Asthma or EIB: Administer in the evening Allergic rhinitis: Individualize administration time to suit patient’s needs Oral granules Administer either directly in the mouth, dissolve in 1 teaspoonful (5 mL) of cold or room temperature baby formula or breast milk, or mix with a spoonful of cold or room temperature soft foods Based on stability studies, only applesauce, carrots, rice, or ice cream should be used Do not open packet until ready to use After opening, the full dose (with or without mixing with baby formula, breast milk, or food) must be administered within 15 min If mixed with baby formula, breast milk, or food, do not store oral granules for future use; discard any unused portion Oral granules are not intended to be dissolved in any liquid other than baby formula or breast milk for administration; however, liquids may be taken subsequent to administration Storage All formulations: Store at 25ºC (77°ºF), excursions permitted to 15-30ºC (59-86ºF) Protect from moisture and light Store in original package BRAND FORM. UNIT PRICE PILL IMAGE montelukast oral- 10 mg tabletmontelukast oral- 10 mg tabletmontelukast oral- 5 mg chewable tabletmontelukast oral- 4 mg chewable tabletmontelukast oral- 4 mg chewable tabletmontelukast oral- 5