AIRFAST 4MG SACHETS

Dosage & Administration

Dosing by Condition

Asthma (6 months-5 years): 4 mg once daily in the evening (one sachet). Allergic rhinitis (6 months-5 years): 4 mg once daily (time of day flexible). Asthma + allergic rhinitis (6 months-5 years): 4 mg once daily in the evening. Exercise-induced bronchoconstriction: approved dosing applies to older children/adults (e.g., 5 mg for 6-14 years or 10 mg for ≥15 years at least 2 hours before exercise), not for 4 mg granules in <6 years.

How to Take

Open the sachet immediately before use and give the entire contents. Administer granules directly into the mouth OR mix with 1 teaspoon (5 mL) of cold/room‑temperature soft food (e.g., applesauce, carrots, rice, ice cream) OR with 5 mL of breast milk or infant formula; give within 15 minutes and do not store for later. Do not mix with any other liquids. For asthma, dose once daily in the evening.

Side Effects

Common Side Effects

Common: headache, abdominal pain, upper respiratory tract infection, fever; also reported (especially in pediatrics): cough, diarrhea, pharyngitis/sore throat, rhinorrhea, otitis media, sinusitis, rash.

Safety & Warnings

Contraindications

Hypersensitivity to montelukast or any component of the product.

Age Restriction

Approved from 6 months of age for perennial allergic rhinitis; approved from 12 months of age for asthma (4 mg oral granules).

Drug Interactions

Drug Interactions

Enzyme inducers (e.g., rifampicin/rifampin, phenobarbital, phenytoin, carbamazepine) may decrease montelukast exposure/efficacy; gemfibrozil (CYP2C8 inhibitor) may increase montelukast exposure.

Special Populations

Pregnancy

Consult Doctor

Breastfeeding

Consult Doctor

Liver Impairment

No dose adjustment needed in mild-to-moderate hepatic impairment; severe hepatic impairment: not adequately studied-use caution/no specific recommendation.

Storage & Patient Advice

Missed Dose

If a dose is missed, skip it and take the next dose at the regular time; do not take a double dose.

Overdose

Expected symptoms include abdominal pain, somnolence, thirst, headache, vomiting, and hyperactivity; treat with supportive/symptomatic care, no specific antidote, and montelukast is not removed by hemodialysis.

Patient Counseling

Give 1 sachet (4 mg) once daily, typically in the evening for asthma control; open immediately before use and give all granules directly in the mouth or mix with a small amount of cold/room-temperature soft food (e.g., applesauce) or a small amount of breast milk/formula, and administer within 15 minutes (do not store the mixture and do not mix into a full bottle or other liquids). This is a controller/preventer and will not treat an acute asthma attack-keep a rescue inhaler available. Monitor for neuropsychiatric symptoms (sleep disturbance, agitation, mood changes, suicidal thoughts) and seek medical advice promptly; do not stop inhaled/oral corticosteroids without prescriber direction. Store below 30°C in the original sachet.

Pharmacology

Mechanism of Action

Selective cysteinyl leukotriene receptor 1 (CysLT1) antagonist that blocks leukotriene D4 (and related cysteinyl leukotrienes), reducing bronchoconstriction, airway edema/inflammation, and mucus secretion.

Onset of Action

Within 1 day for symptom improvement; full benefit may take several days.

Duration of Effect

Approximately 24 hours.

Bioavailability

Oral bioavailability is approximately 64% (adult data for the 10 mg film-coated tablet); pediatric 4 mg granules have comparable systemic exposure to the 4 mg chewable tablet when administered as directed, but a single fixed % for granules is not definitively established across all conditions.

Excretion

Primarily excreted via bile into feces (about 86% in feces); urinary excretion is negligible (<0.2%).

Protein Binding

>99%.

Product Information

Available Dosage Forms

Oral granules (sachets), chewable tablets, and film‑coated tablets.

Symptom Target

Allergy, Congestion, Runny Nose

Sedating

No

Reviewed by Al Mujtama Pharmacy Medical Review Team. Last reviewed 09-05-2026