SIGULAIR 10/MG FC TAB 28/TAB

Indications

Approved Uses

Asthma: prophylaxis and chronic treatment (including prevention of daytime and nighttime symptoms). Exercise‑induced bronchoconstriction (EIB): prevention. Allergic rhinitis: relief of symptoms of seasonal allergic rhinitis and perennial allergic rhinitis (age cutoffs depend on formulation/strength; the 10 mg film‑coated tablet is for older adolescents/adults).

Dosage & Administration

Dosing by Condition

Adults/adolescents (typically ≥15 years) using the 10 mg film‑coated tablet: Asthma: 10 mg once daily in the evening. Allergic rhinitis (seasonal or perennial): 10 mg once daily (time can be individualized). EIB prevention: 10 mg at least 2 hours before exercise; do not repeat within 24 hours and do not add an extra dose if on daily therapy.

Initial Dose

10mg once daily in the evening

Maintenance Dose

10mg once daily.

Maximum Dose

10mg per 24 hours.

Children's Dosage

This is the 10mg film-coated tablet formulation for patients 15 years and older; pediatric dosages use other formulations: Asthma/Allergic Rhinitis: (6-14 years) 5mg chewable once daily; (2-5 years) 4mg chewable or granules once daily; (12-23 months for asthma, 6-23 months for perennial allergic rhinitis) 4mg oral granules once daily. Exercise-Induced Bronchoconstriction: (6-14 years) 5mg chewable at least 2 hours before exercise.

Dose Adjustment Notes

No dose titration is required. No dosage adjustment is needed in the elderly or in renal impairment; no adjustment is needed in mild to moderate hepatic impairment (avoid/use caution in severe hepatic impairment due to limited data).

How to Take

Oral: swallow the 10 mg film‑coated tablet with water once daily. For asthma, dose once daily in the evening. For allergic rhinitis, dose once daily at any time of day. May be taken with or without food. For prevention of exercise‑induced bronchoconstriction (EIB), take a single dose at least 2 hours before exercise; do not take an additional dose within 24 hours if already on once‑daily therapy.

Side Effects

Common Side Effects

Common adverse effects include headache and abdominal pain; also reported commonly are upper respiratory infection symptoms (e.g., cough, fever, sore throat/rhinorrhea) and diarrhea.

Side Effect Frequency

Common (≥1%): headache, abdominal pain (and in some datasets: upper respiratory infection, cough, fever). Important serious/rare: neuropsychiatric events (frequency not reliably quantifiable; boxed warning), hypersensitivity including anaphylaxis/angioedema, eosinophilic granulomatosis with polyangiitis (Churg-Strauss), and hepatic injury (including cholestatic hepatitis).

Safety & Warnings

Contraindications

Hypersensitivity to montelukast (montelukast sodium) or to any component/excipient of the formulation.

Warnings & Precautions

Not for acute asthma attacks; counsel/monitor for neuropsychiatric symptoms (boxed warning); do not abruptly substitute for inhaled/oral corticosteroids; aspirin-sensitive asthma patients should continue to avoid aspirin/NSAIDs; EGPA has been reported (often with steroid reduction).

Age Restriction

SINGULAIR (montelukast) 10 mg film‑coated tablet is indicated for adolescents and adults (≥15 years); younger children require age-appropriate strengths/forms (e.g., 4 mg/5 mg).

Drug Interactions

Drug Interactions

CYP inducers (e.g., rifampin, phenobarbital, phenytoin, carbamazepine) can decrease montelukast exposure/efficacy; strong CYP2C8 inhibitors (e.g., gemfibrozil) can increase montelukast exposure.

Food Interaction

No clinically meaningful food restriction; may be taken with or without food.

Special Populations

Pregnancy

Consult Doctor

Breastfeeding

Consult Doctor

Children

This is the 10mg film-coated tablet formulation for patients 15 years and older; pediatric dosages use other formulations: Asthma/Allergic Rhinitis: (6-14 years) 5mg chewable once daily; (2-5 years) 4mg chewable or granules once daily; (12-23 months for asthma, 6-23 months for perennial allergic rhinitis) 4mg oral granules once daily. Exercise-Induced Bronchoconstriction: (6-14 years) 5mg chewable at least 2 hours before exercise.

Elderly

Standard adult dosing.

Kidney Impairment

No adjustment needed.

Liver Impairment

No dose adjustment needed in mild-to-moderate hepatic impairment; severe hepatic impairment has not been adequately studied-use with caution.

Storage & Patient Advice

Missed Dose

If a dose is missed, take it when remembered the same day; if it is close to the next dose, skip the missed dose and resume the regular schedule-do not double doses.

Stopping the Medicine

Do not stop or change asthma therapy without clinician advice; montelukast can be discontinued without taper, but stopping may worsen asthma/allergy control.

Overdose

Overdose is usually managed with supportive care; reported symptoms include abdominal pain, somnolence, thirst, headache, vomiting, and psychomotor hyperactivity; no specific antidote and not expected to be removed by hemodialysis-seek urgent medical advice/poison center.

Patient Counseling

Take 10 mg by mouth once daily; for asthma it is commonly taken in the evening, and for allergic rhinitis it may be taken at any time. Take with or without food. Use regularly even when you feel well. Not for relief of an acute asthma attack-keep a fast-acting rescue inhaler available. Do not stop or reduce other asthma medicines (especially inhaled corticosteroids) unless your prescriber tells you. Seek medical advice promptly for new or worsening mood/behavior changes (e.g., agitation, depression, abnormal dreams/insomnia, suicidal thoughts) due to the boxed warning; report hypersensitivity symptoms as well.

Monitoring Requirements

Monitor for neuropsychiatric symptoms (e.g., agitation, sleep disturbance, depression, suicidal ideation/behavior) and overall asthma/allergic rhinitis control; no routine laboratory monitoring is required.

Pharmacology

Mechanism of Action

Selective cysteinyl leukotriene receptor 1 (CysLT1) antagonist that blocks leukotriene (LTC4, LTD4, LTE4) signaling, reducing bronchoconstriction, airway edema/inflammation, and mucus secretion.

Onset of Action

Clinical effect on asthma parameters can occur within 1 day of starting therapy; maximal benefit may take several days of continued use.

Duration of Effect

Approximately 24 hours.

Bioavailability

Mean oral bioavailability (10 mg film-coated tablet): ~64%.

Excretion

Excretion primarily via bile into feces (~86% recovered in feces); minimal urinary excretion (<0.2% recovered in urine).

Protein Binding

>99%.

Product Information

Available Dosage Forms

Film‑coated tablet (10 mg), chewable tablets (4 mg, 5 mg), and oral granules (4 mg).

Composition per Dose

Each film-coated tablet: 10.4mg montelukast sodium equivalent to 10mg montelukast

Generic Availability

Yes

Symptom Target

Asthma, Exercise-Induced Bronchoconstriction, Allergic Rhinitis

Sedating

No

Reviewed by Al Mujtama Pharmacy Medical Review Team. Last reviewed 02-05-2026