Montelukast

SINGULAIR

Open Montelukast in the interactive console ↗

Pronunciation: mon-te-LOO-kast (SING-yoo-lair)

Montelukast ballicule: receptor binding, kinetics and half-life diagram — Mechanism of action: Montelukast ballicule

Montelukast SINGULAIR mascot mnemonic cartoon — Visual mnemonic: Montelukast mascot
**“Monte’s leukotriene Singularity”**

What it isCysLT1 leukotriene-receptor antagonist; asthma and allergic rhinitis.

Why this oneConvenient use and broad age-range formulations make it the dominant leukotriene antagonist, especially for aspirin-exacerbated disease.

What limits itIt is weaker than inhaled steroids. Serious mood, behavior and sleep effects can emerge; ask directly and stop it if they appear.

Montelukast molecular structure (skeletal formula) — Molecular structure: Montelukast

FDA-approved for

asthma/allergic rhinitis (1998)

FDA label

Read the full label on DailyMed ↗

BOXED WARNING Serious neuropsychiatric events (agitation, aggression, depression, suicidal thoughts/behavior); reserve for allergic rhinitis patients with inadequate response or intolerance to alternative therapies.

FDA dosing	Population	Start
Asthma	≥15 yr	10 mg QHS
Exercise-induced bronchoconstriction	≥15 yr	10 mg ≥2 h before exercise PRN
Seasonal allergic rhinitis	≥15 yr	10 mg QD
Perennial allergic rhinitis	≥15 yr	10 mg QD

Renal No adjustment needed

Hepatic No adjustment needed in mild–moderate impairment.

EIB: do not take an additional dose within 24 h of a previous dose.

Instructions

For asthma (or asthma plus allergic rhinitis), take once daily in the evening.
For EIB, take a single dose ≥2 h before exercise; do not repeat within 24 h and do not take if already on daily montelukast.
Do not use to treat acute asthma; keep rescue medication available.
Do not abruptly substitute for inhaled or oral corticosteroids.

Available strengths

tab 10 mg
chew tab 4, 5 mg

Cautions

Neuropsychiatric events
Not for acute asthma/status asthmaticus
Do not abruptly substitute for corticosteroids
Continue aspirin/NSAID avoidance in aspirin-sensitive patients
Eosinophilic conditions/Churg-Strauss syndrome

Adverse reactions

Upper respiratory infection
Fever
Headache
Pharyngitis
Cough
Abdominal pain
Diarrhea
Otitis media
Influenza
Rhinorrhea
Sinusitis

Pregnancy No established drug-associated risk of major birth defects.

Lactation Present in human milk; available data do not suggest a significant risk of adverse reactions.

Cost

Montelukast (SINGULAIR)

What pharmacies pay · NADAC 9/30/26

Strength		#/mo	generic $/mo	CostPlus
10 mg	tab	30 qd	$1.26	offered
4 mg	chew tab	30 qd	$2.26	offered
5 mg	chew tab	30 qd	$2.11	offered

Generic entry2012

⚠ BOXED WARNING

Serious neuropsychiatric events

Classes and tags

Clinical profile

Therapeutic safety burden1 / 4

Overdose danger2 / 4

Weight-gain liability0 / 4

Sedation liability0 / 4

QT / Torsades0 / 4

Direct muscarinic antagonism0 / 4

Embryofetal risk1 / 4

Legacy pregnancy categoryB

Defining liabilityTremor, tachycardia or anticholinergic effects; excessive beta-agonist exposure can cause hypokalemia and arrhythmia.

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Memory aids: interaction avatars

CYP2C8 substrate

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