AIRFAST 5mg Tablets/Chewable

What is AIRFAST 5mg

AIRFAST 5 mg is the brand name for chewable tablets containing montelukast sodium 5 mg, a selective leukotriene-receptor antagonist (LTRA) used in the prophylaxis and long-term control of asthma and to relieve seasonal or perennial allergic rhinitis. By blocking the cysteinyl-leukotriene receptor 1 (CysLT₁) in the airway and nasal mucosa, montelukast prevents bronchoconstriction, mucus hyper-secretion, and airway inflammation triggered by allergens, irritants, cold air, or exercise.

• Therapeutic class: Anti-asthmatic, Anti-allergic (LTRA).
• Indications:
  • Maintenance treatment of persistent asthma (mild, moderate, or severe) in adults and children ≥ 6 months.
  • Prevention of exercise-induced bronchoconstriction (EIB) in patients ≥ 6 years.
  • Symptomatic relief of seasonal and perennial allergic rhinitis.
• Pharmaceutical form: Chewable tablet, strawberry-flavored, scored; lactose-free and gluten-free.
• Packaging: Blister pack 10 tablets × 3 (total 30) in a moisture-resistant carton.
• Regulatory status: Prescription-only medicine (Rx).
• Key benefits: Once-daily dosing, rapid onset within 2 h, steroid-sparing effect in asthma, no sedation, safe in aspirin-sensitive asthma.
• Limitations: Not indicated for acute asthma attacks; slower onset than short-acting β₂-agonists for EIB; neuropsychiatric vigilance required.

How to use AIRFAST 5mg

Correct administration optimizes therapeutic benefit and minimizes adverse events.

• Dose & timing: One 5 mg chewable tablet once daily in the evening, taken at least 2 h before physical activity when used for EIB-prophylaxis. Evening dosing aligns with the circadian rise in leukotrienes.
• Administration method: Chew thoroughly before swallowing; may be taken with or without food. Follow with a sip of water.
• Missed dose: If < 12 h late, take as soon as remembered; if > 12 h, skip and resume usual schedule—do not double doses.
• Asthma action plan: Continue inhaled corticosteroid (ICS) or controller therapy; do not substitute AIRFAST abruptly for ICS. Keep rescue inhaler (SABA) accessible for acute bronchospasm.
• Pediatric guidance: For children 6–14 years, the 5 mg chewable form is preferred; ensure supervision to prevent choking and verify complete chewing.
• Peri-operative use: Continue therapy; no specific withholding period required.
• Monitoring: Review control every 4–8 weeks; assess peak flow, symptom-free nights, reliever use, and allergen exposure.
• Lifestyle advice: Avoid smoking; implement allergen avoidance strategies; maintain vaccination schedule (influenza, pneumococcal).

Mode of Action AIRFAST 5mg

Montelukast selectively inhibits the binding of cysteinyl-leukotrienes (LTC₄, LTD₄, and LTE₄) to the CysLT₁ receptor located on bronchial smooth muscle, eosinophils, macrophages, and endothelial cells.

• Leukotriene blockade: Prevents leukotriene-induced bronchoconstriction, mucosal edema, vascular permeability, and eosinophil recruitment.
• Anti-inflammatory profile: Reduces airway eosinophilia, serum IgE, and pro-inflammatory cytokines (IL-4, IL-5).
• No β-adrenergic activity: Avoids tachyphylaxis associated with chronic β₂-agonist use and suitable for patients intolerant to sympathomimetics.
• Pharmacokinetics:
  • Oral bioavailability ≈ 64%; peak plasma in 2–3 h.
  • Highly protein-bound (≥ 99%).
  • Extensive hepatic CYP3A4 and CYP2C9 metabolism; inactive metabolites excreted in bile.
  • Terminal half-life 2.7–5.5 h; effect persists ≥ 24 h, permitting once-daily dosing.
• Clinical implications: Improves FEV₁, reduces nighttime awakenings, lowers rescue inhaler use, and prevents EIB within 2 h of dosing.
• Extrapulmonary benefits: Diminishes nasal congestion, rhinorrhoea, and sneezing in allergic rhinitis by acting on nasal mucosa leukotriene receptors.
• Steroid-sparing: May allow ICS dose reduction in well-controlled asthma, minimizing systemic corticosteroid exposure.

AIRFAST 5mg Interactions AIRFAST 5mg

Montelukast is primarily a substrate of hepatic CYP3A4 and CYP2C9; clinically relevant interactions are uncommon but vigilance is prudent.

• Enzyme inducers:
  • Rifampicin, phenobarbital, phenytoin, carbamazepine increase CYP activity → ↓ montelukast plasma levels (30-60%) → possible loss of efficacy; consider dose monitoring or alternative agent.
• Enzyme inhibitors: Strong CYP3A4 inhibitors (ketoconazole, clarithromycin, ritonavir) have negligible effect on montelukast exposure; no adjustment required.
• Warfarin: Studies show no clinically important change in INR, but isolated reports of altered coagulation exist; monitor INR when initiating or discontinuing AIRFAST.
• Gemfibrozil: May double montelukast AUC via OATP inhibition; not clinically significant but observe for neuropsychiatric events.
• Biologics (omalizumab, mepolizumab): Concomitant use is safe and may be complementary in severe asthma.
• Food & herbal supplements: Grapefruit juice has minimal effect; St John’s wort (CYP3A4 inducer) may lower levels—avoid concurrent use.
• Alcohol & CNS depressants: No pharmacokinetic interaction, but additive neuropsychiatric adverse effects (insomnia, agitation) may occur; caution advised.
• Vaccines: No interference with immune response; continue routine immunisation.

Dosage of AIRFAST 5mg

Dosing must be individualized based on age, clinical response, and concomitant therapy.

• Standard dosage (6–14 years): 5 mg chewable tablet once daily in the evening.
• Adults & adolescents ≥ 15 years: 10 mg film-coated tablet once daily (use appropriate strength).
• Prophylaxis of EIB: 5 mg (children) or 10 mg (adults) taken ≥ 2 h before exercise; do not repeat within 24 h.
• Allergic rhinitis: Same dose as asthma; may be started or discontinued based on allergen season.
• Renal impairment: No dose adjustment—minimal renal clearance.
• Hepatic impairment: Mild-to-moderate: no adjustment; severe hepatic insufficiency: use with caution, limited data.
• Elderly (≥ 65 years): Pharmacokinetics comparable to younger adults; standard dose appropriate.
• Dose escalation: Doses > 10 mg daily show no additional benefit and increase adverse effects—do not exceed recommended maximum.
• Treatment duration: Continue long-term to maintain control; reassess need every 6–12 months.

Possible side effects of AIRFAST 5mg

Montelukast is generally well tolerated; most adverse reactions are mild and transient.

• Common (≥ 1%):
  • Headache, abdominal pain, dyspepsia.
  • Upper respiratory infection, cough, pharyngitis.
  • Diarrhoea, nausea, vomiting.
• Uncommon (< 1%):
  • Rash, eczema, pruritus.
  • Asthenia, fatigue, pyrexia.
• Neuropsychiatric: Insomnia, agitation, anxiety, dream abnormalities, irritability; rare reports of hallucinations, depression, suicidal thinking—counsel caregivers and discontinue if severe.
• Hypersensitivity: Urticaria, angio-oedema, anaphylaxis (rare); stop immediately and treat per anaphylaxis protocol.
• Eosinophilic systemic features (Churg–Strauss syndrome): Occurs mainly during corticosteroid tapering; watch for fever, vasculitic rash, neuropathy.
• Hepatic: Elevations of ALT/AST, cholestatic hepatitis; monitor LFTs if symptoms (jaundice, right-upper-quadrant pain) appear.
• Others: Palpitations, bruising, arthralgia, myalgia, thrombocytopenia—very rare.
• Management: Most mild reactions resolve without therapy; severe events warrant discontinuation and specialist review.

AIRFAST 5mg Contraindications AIRFAST 5mg

• Known hypersensitivity to montelukast, any LTRA, or tablet excipients (mannitol, aspartame, red iron oxide).
• Phenylketonuria: Chewable tablets contain aspartame (source of phenylalanine) 0.842 mg per dose—avoid in patients with PKU.
• Acute asthma exacerbation: Not for reversal of status asthmaticus; use rapid-acting β₂-agonist and systemic corticosteroid.
• Severe hepatic impairment (Child–Pugh C): Limited clinical data; avoid use.
• Previous neuropsychiatric reaction clearly linked to montelukast (e.g., suicidal ideation); rechallenge discouraged.
• Concomitant use of strong CYP3A4 inducers in patients whose asthma is unstable despite maximal therapy—therapeutic failure likely.
• Breast-feeding caution: Montelukast is excreted in breast milk in low concentrations; use only if benefits outweigh risks.

Storage of AIRFAST 5mg

• Temperature: Store below 30 °C (86 °F); brief excursions up to 40 °C permissible (< 48 h) without loss of potency.
• Humidity: Keep in original foil blisters until use; montelukast is hygroscopic and degrades with moisture.
• Light protection: Protect from direct sunlight; active ingredient is photosensitive at high intensities.
• Child safety: Child-resistant carton; keep out of sight and reach of children.
• Transport: Avoid freezing and excessive heat during shipment; use insulated packaging if ambient > 40 °C.
• Shelf life: 36 months from date of manufacture when stored as recommended; check expiry date printed on carton and blister.
• Disposal: Do not flush unused tablets; mix with undesirable substance (coffee grounds), place in sealed bag, and discard per local regulations or return to pharmacy take-back program.