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Montelukast Drug Information Provided by Lexi-Comp

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This information has been developed and provided by an independent third-party source. Merck & Co., Inc. does not endorse and is not responsible for the accuracy of the content, or for practices or standards of non-Merck sources.

Special Alerts

Montelukast (Singulair®) and the Possible Association With Behavior/Mood Changes and Suicide - March 2008

The Food and Drug Administration (FDA) is informing healthcare professionals of the possible association between montelukast (Singulair®) use and suicidality (suicidal thinking and behavior), suicide, and behavior or mood changes. This review is ongoing and the FDA will continue to work with Merck & Co, Inc. to further evaluate this possible association of suicidality with montelukast use. The analysis is expected to take up to 9 months before completion. After the completed evaluation, the FDA will communicate any final conclusions to the public. The FDA is also reviewing postmarketing reports of behavior/mood changes, suicidality, and suicide received with other leukotriene-modifying medications, including zafirlukast (Accolate®) and zileuton (Zyflo®, Zyflo CR™), to determine if further evaluation of these agents is necessary. Patients should not discontinue Singulair® therapy and should discuss any concerns with their healthcare provider. Healthcare professionals and caregivers should monitor for any changes in behavior or mood in patients receiving montelukast.

Additional information can be found at

http://www.fda.gov/medwatch/safety/2008/safety08.htm#Singulair

Medication Safety Issues

Sound-alike/look-alike issues:

Singulair® may be confused with Sinequan®

Pronunciation

(mon te LOO kast)

U.S. Brand Names

  • Singulair®

Index Terms

  • Montelukast Sodium

Generic Available

No

Canadian Brand Names

  • Singulair®

Pharmacologic Category

  • Leukotriene Receptor Antagonist

Pharmacologic Category Synonyms

  • LTRA

Use: Labeled Indications

Prophylaxis and chronic treatment of asthma; relief of symptoms of seasonal allergic rhinitis and perennial allergic rhinitis; prevention of exercise-induced bronchospasm

Use: Unlabeled/Investigational

Acute asthma

Pregnancy Risk Factor

B

Pregnancy Considerations

Montelukast was not teratogenic in animal studies, however, there are no adequate and well-controlled studies in pregnant women. Use during pregnancy only if clearly needed. Based on limited data, structural defects have been reported in neonates exposed to montelukast in utero, however, a specific pattern and relationship to montelukast has not been established. Healthcare providers should report any prenatal exposures to the montelukast pregnancy registry at (800) 986-8999.

Lactation

Excretion in breast milk unknown/use caution

Breast-Feeding Considerations

Zafirlukast, another leukotriene receptor antagonist, is excreted in breast milk and use while breast-feeding is not recommended.

Contraindications

Hypersensitivity to montelukast or any component of the formulation

Warnings/Precautions

Concerns related to adverse effects:

• Eosinophilia and vasculitis: In rare cases, patients may present with systemic eosinophilia, sometimes presenting with clinical features of vasculitis consistent with Churg-Strauss syndrome, a condition which is often treated with systemic corticosteroid therapy. Healthcare providers should be alert to eosinophilia, vasculitic rash, worsening pulmonary symptoms, cardiac complications, and/or neuropathy presenting in their patients. A causal association between montelukast and these underlying conditions has not been established.

Concurrent drug therapy issues:

• Corticosteroids: Appropriate clinical monitoring and caution are recommended when systemic corticosteroid reduction is considered in patients receiving montelukast.

Special populations:

• Pediatrics: Safety and efficacy have not been established in children <6 months of age.

Dosage form specific issues:

• Chewable tablet: Contains phenylalanine.

Other warnings/precautions:

• Aspirin-sensitive asthmatics: Montelukast will not interrupt bronchoconstrictor response to aspirin or other NSAIDs. Patients with known aspirin sensitivity should continue to avoid these agents.

• Reversal of bronchospasm: Not FDA approved for use in the reversal of bronchospasm in acute asthma attacks, including status asthmaticus. Some clinicians, however, support its use (Cylly, 2003; Camargo, 2003; Ferreira, 2001). Appropriate rescue medication should be available.

Adverse Reactions

(As reported in adults)

1% to 10%:

Central nervous system: Dizziness (2%), fatigue (2%), fever (2%)

Dermatologic: Rash (2%)

Gastrointestinal: Abdominal pain (3%), dyspepsia (2%), dental pain (2%), gastroenteritis (2%)

Hepatic: AST increased (2%)

Neuromuscular & skeletal: Weakness (2%)

Respiratory: Cough (3%), nasal congestion (2%)

Postmarketing and/or case reports: Aggression, agitation, anaphylaxis, angioedema, arthralgia, behavior/mood changes, bleeding tendency, bruising, cholestasis (rare), Churg-Strauss syndrome (rare), depression, diarrhea, dream abnormalities, drowsiness, dyspepsia, edema, eosinophilia (systemic; rare), erythema nodosum, hallucinations, hepatic eosinophilic infiltration (rare); hepatitis (mixed pattern, hepatocellular, and cholestatic); hypersensitivity, hypoesthesia, insomnia, irritability, muscle cramps, myalgia, nausea, palpitation, pancreatitis (rare), paresthesia, pruritus, psychomotor hyperactivity, restlessness, seizure (rare), suicidal thinking/behavior (suicidality), suicide, tremor, urticaria, vasculitis (rare), vomiting

Metabolism/Transport Effects

Substrate (major) of CYP2C9, 3A4; Inhibits CYP2C8 (weak), 2C9 (weak)

Drug Interactions

CYP2C9 Inducers (Highly Effective): May increase the metabolism of CYP2C9 Substrates (High risk). Risk C: Monitor therapy

CYP2C9 Inhibitors (Moderate): May decrease the metabolism of CYP2C9 Substrates (High risk). Risk C: Monitor therapy

CYP2C9 Inhibitors (Strong): May decrease the metabolism of CYP2C9 Substrates (High risk). Risk D: Consider therapy modification

CYP3A4 Inducers (Strong): May increase the metabolism of CYP3A4 Substrates. Risk C: Monitor therapy

Herbs (CYP3A4 Inducers): May increase the metabolism of CYP3A4 Substrates. Risk C: Monitor therapy

Ethanol/Nutrition/Herb Interactions

Herb/Nutraceutical: St John's wort may decrease montelukast levels.

Storage

Store at room temperature of 15°C to 30°C (59°F to 86°F). Protect from moisture and light.

Granules: Use within 15 minutes of opening packet.

Mechanism of Action

Selective leukotriene receptor antagonist that inhibits the cysteinyl leukotriene receptor. Cysteinyl leukotrienes and leukotriene receptor occupation have been correlated with the pathophysiology of asthma, including airway edema, smooth muscle contraction, and altered cellular activity associated with the inflammatory process, which contribute to the signs and symptoms of asthma. Cysteinyl leukotrienes are also released from the nasal mucosa following allergen exposure leading to symptoms associated with allergic rhinitis.

Pharmacodynamics/Kinetics

Duration: >24 hours

Absorption: Rapid

Distribution: Vd: 8-11 L

Protein binding, plasma: >99%

Metabolism: Extensively hepatic via CYP3A4 and 2C9

Bioavailability: Tablet: 10 mg: Mean: 64%; 5 mg: 63% to 73%

Half-life elimination, plasma: Mean: 2.7-5.5 hours

Time to peak, serum: Tablet: 10 mg: 3-4 hours; 5 mg: 2-2.5 hours; 4 mg: 2 hours

Excretion: Feces (86%); urine (<0.2%)

Dosage

Oral:

Children:

6-11 months: Asthma (unlabeled use): 4 mg (oral granules) once daily, taken in the evening

6-23 months: Perennial allergic rhinitis: 4 mg (oral granules) once daily

12-23 months: Asthma: 4 mg (oral granules) once daily, taken in the evening

2-5 years: Asthma, seasonal or perennial allergic rhinitis: 4 mg (chewable tablet or oral granules) once daily, taken in the evening

6-14 years: Asthma, seasonal or perennial allergic rhinitis: 5 mg (chewable tablet) once daily, taken in the evening

Children ?15 years and Adults:

Asthma, seasonal or perennial allergic rhinitis: 10 mg/day, taken in the evening

Asthma, acute (unlabeled use): 10 mg as a single dose administered with first-line therapy

Bronchoconstriction, exercise-induced (prevention): 10 mg at least 2 hours prior to exercise; additional doses should not be administered within 24 hours. Daily administration to prevent exercise-induced bronchoconstriction has not been evaluated.

Dosing adjustment in renal impairment: No adjustment necessary

Dosing adjustment in hepatic impairment: Mild-to-moderate: No adjustment necessary. Patients with severe hepatic disease were not studied.

Administration: Oral

When treating asthma, administer dose in the evening. Patients with allergic rhinitis may individualize administration time. Granules may be administered directly in the mouth or mixed with applesauce, carrots, rice, ice cream, baby formula, or breast milk; do not add to any other liquids. Administer within 15 minutes of opening packet.

Monitoring Parameters

Mood or behavior changes, including suicidal thinking/behavior

Dietary Considerations

Tablet, chewable: 4 mg strength contains phenylalanine 0.674 mg; 5 mg strength contains phenylalanine 0.842 mg

Patient Education

Do not stop other asthma medication unless advised by prescriber. Chewable tablet contains phenylalanine. Take every evening on a continuous basis; do not discontinue even if feeling better (this medication may help reduce incidence of acute attacks). Granules may be administered directly in the mouth or mixed with applesauce, carrots, rice, ice cream, baby formula, or breast milk (do not add to any other liquids); administer within 15 minutes of opening packet. You may experience mild headache (mild analgesic may help); or fatigue or dizziness (use caution when driving). Report skin rash or itching, abdominal pain or persistent GI upset, unusual cough or congestion, behavior and mood changes including suicide thoughts, feeling of numbness in arms or legs, flu-like illness, or worsening of asthmatic condition. Pregnancy/breast-feeding precautions: Inform prescriber if you are or intend to become pregnant. Consult prescriber if breast-feeding.

Geriatric Considerations

The pharmacokinetic profile in the elderly is similar to younger adults except the half-life is slightly longer in the elderly. Despite this difference, no adjustment in dose is necessary in the elderly. Elimination is mostly fecal and bile with insignificant amounts from renal elimination, which is an advantage for the elderly.

Dental Health: Effects on Dental Treatment

Key adverse event(s) related to dental treatment: Dental pain.

Dental Health: Vasoconstrictor/Local Anesthetic Precautions

No information available to require special precautions

Mental Health: Effects on Mental Status

May cause dizziness or drowsiness

Mental Health: Effects on Psychiatric Treatment

Barbiturates may decrease the effects of montelukast; CYP3A4 substrate; nefazodone may increase effects

Nursing: Physical Assessment/Monitoring

Not for use in acute asthma attacks, including status asthmaticus. Assess effectiveness and interactions of other medications patient may be taking. Monitor mental and mood status. Be alert to thoughts of suicide. Monitor effectiveness of therapy and adverse reactions at beginning of therapy and periodically with long-term use. Assess knowledge/teach patient appropriate use, interventions to reduce side effects, and adverse symptoms to report.

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Granules:

Singulair®: 4 mg/packet (30s)

Tablet:

Singulair®: 10 mg

Tablet, chewable:

Singulair®: 4 mg [contains phenylalanine 0.674 mg; cherry flavor]; 5 mg [contains phenylalanine 0.842 mg; cherry flavor]

Pricing: U.S. (www.drugstore.com)

Chewable (Singulair)

4 mg (30): $108.01

5 mg (30): $105.99

Pack (Singulair)

4 mg (30): $116.48

Tablets (Singulair)

10 mg (30): $112.25

References

Bakhireva LN, Jones KL, and Chamber CD, “Safety of Leukotriene Receptor Antagonists in Pregnancy,” Birth Defects Res A Clin Mol Teratol, 2006, 76(5): 314. From “Abstracts of the 46th Teratology Society Annual Meeting, 30th Annual Meeting of the Neurobehavioral Teratology Society, 19th International Conference of the Organization of Teratology Information Specialists,” Birth Defects Res A Clin Mol Teratol, 2006, 76(5):313-428.

Camargo CA Jr, Smithline HA, Malice MP, et al, “A Randomized Controlled Trial of Intravenous Montelukast in Acute Asthma,” Am J Respir Crit Care Med, 2003, 167(4):528-33.

Cylly A, Kara A, Ozdemir T, et al, “Effects of Oral Montelukast on Airway Function in Acute Asthma,” Respir Med, 2003, 97(5):533-6.

Ferreira MB, Santos AS, Pregal AL, et al, “Leukotriene Receptor Antagonists (Montelukast) in the Treatment of Asthma Crisis: Preliminary Results of a Double-Blind Placebo Controlled Randomized Study,” Allerg Immunol (Paris), 2001, 33(8):315-8.

Sarkar M and Koren G, “Pregnancy Outcome Following Gestational Exposure to Montelukast: A Prospective Controlled Study,” Clin Pharmacol Ther, 2005, 77(2):30. From “Abstracts of the American Society for Clinical Pharmacology and Therapeutics Annual Meeting,” Clin Pharmacol Ther, 2005, 77(2):1-146.

International Brand Names

  • Kastair (PH)
  • Kipres (JP)
  • Montair (IN, PH)
  • Montemax (PH)
  • Montiget (PH)
  • Singulair (AR, AT, AU, BE, BG, BO, BR, CH, CL, CN, CO, CR, CZ, DE, DK, DO, EC, EE, ES, FI, FR, GB, GT, HK, HN, HU, IE, IL, IT, KP, MX, MY, NI, NL, NO, PA, PE, PH, PK, PL, PR, PY, SE, SG, SV, TH, TW, UY, VE)
  • Singulair Chew (KP)

Lexi-Comp.com

Last full review/revision August 2008

Content last modified August 2008

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