Schedule H

Oral

Form Strengths Available

Film-coated tablets 10 mg

Chewable tablets 4 mg, 5 mg

Oral granules (sachets) 4 mg

INDICATIONS + DOSING — FOR CLINICIAN USE ONLY

Primary Indications (Approved / Standard in India)

1. Chronic Persistent Asthma (Mild to Moderate) — As Add-on Therapy

Parameter Recommendation

Starting dose 10 mg once daily in the evening

Titration Not applicable

Usual maintenance dose 10 mg once daily

Maximum dose 10 mg/day

Clinical notes Add-on to inhaled corticosteroids (ICS); NOT a substitute for ICS; NOT for acute bronchospasm relief; continue other asthma controller medications; particularly useful in aspirin-exacerbated respiratory disease (AERD)

1. Allergic Rhinitis (Seasonal and Perennial)

Parameter Recommendation

Starting dose 10 mg once daily

Titration Not applicable

Usual maintenance dose 10 mg once daily

Maximum dose 10 mg/day

Duration Seasonal: during allergen season; Perennial: continuous as needed

Clinical notes Evening administration preferred; can be used alone or with antihistamines; for seasonal rhinitis, start 1–2 days before expected allergen exposure if predictable

1. Exercise-Induced Bronchoconstriction (EIB) — Prophylaxis

Parameter Recommendation

Starting dose 10 mg as single dose

Titration Not applicable

Usual maintenance dose 10 mg at least 2 hours before exercise

Maximum dose 10 mg in 24 hours

Clinical notes NOT for treatment of acute bronchospasm; do not repeat dose within 24 hours; if already on daily montelukast for another indication, no additional dose required before exercise

1. Asthma with Concomitant Allergic Rhinitis

Parameter Recommendation

Starting dose 10 mg once daily in the evening

Titration Not applicable

Usual maintenance dose 10 mg once daily

Maximum dose 10 mg/day

Clinical notes Single agent addresses both conditions; particularly beneficial when both conditions coexist; continue ICS for asthma control

Secondary Indications — Adults (Off-label)

Indication Dose Duration Evidence Notes

Chronic spontaneous urticaria (antihistamine-refractory) 10 mg once daily 4–12 weeks trial; continue if responding RCTs; Indian dermatology/allergy practice OFF-LABEL; Specialist only; add-on to second-generation antihistamines

Aspirin-exacerbated cutaneous disease (AECD) 10 mg once daily Long-term Case series; specialist practice OFF-LABEL; Specialist only; may reduce aspirin sensitivity

Nasal polyposis (adjunctive) 10 mg once daily Months; long-term Small RCTs; Indian ENT practice OFF-LABEL; Specialist only; used with intranasal steroids; modest benefit

Atopic dermatitis (adjunctive) 10 mg once daily 8–12 weeks trial Limited RCT data OFF-LABEL; Specialist only; inconsistent benefit; consider if prominent pruritus

Post-infectious cough 10 mg once daily 2–4 weeks Limited evidence; Indian pulmonology practice OFF-LABEL; May reduce cough hypersensitivity

PAEDIATRIC DOSING (Specialist Only)

⚠️ Age and Safety Statement

• Minimum age for asthma: 6 months

• Minimum age for allergic rhinitis: 2 years

• Minimum age for exercise-induced bronchoconstriction: 6 years

• Below these ages: Use only under specialist supervision for exceptional circumstances

• Neuropsychiatric monitoring mandatory in all paediatric patients

Primary Paediatric Indications

1. Chronic Persistent Asthma (Mild to Moderate)

6 months – 5 years Oral granules 4 mg OR Chewable tablet 4 mg 4 mg once daily in evening Not applicable 4 mg once daily 4 mg/day

6 – 14 years Chewable tablet 5 mg 5 mg once daily in evening Not applicable 5 mg once daily 5 mg/day

≥15 years Film-coated tablet 10 mg 10 mg once daily in evening Not applicable 10 mg once daily 10 mg/day

Administration Notes:

• Oral granules: Administer directly in mouth OR mix with one spoonful of soft food (applesauce, mashed banana, rice cereal, ice cream) — use within 15 minutes; do not dissolve in liquid

• Chewable tablets: Must be chewed thoroughly before swallowing

• Film-coated tablets: Swallow whole; do not chew

1. Allergic Rhinitis (Seasonal and Perennial)

2 – 5 years Oral granules 4 mg OR Chewable tablet 4 mg 4 mg once daily Not applicable 4 mg once daily 4 mg/day

6 – 14 years Chewable tablet 5 mg 5 mg once daily Not applicable 5 mg once daily 5 mg/day

≥15 years Film-coated tablet 10 mg 10 mg once daily Not applicable 10 mg once daily 10 mg/day

Clinical Note: Not approved for allergic rhinitis below 2 years of age

1. Exercise-Induced Bronchoconstriction (Prophylaxis)

6 – 14 years Chewable tablet 5 mg 5 mg at least 2 hours before exercise Do not repeat within 24 hours

≥15 years Film-coated tablet 10 mg 10 mg at least 2 hours before exercise Do not repeat within 24 hours

Clinical Note: Not approved for EIB prophylaxis below 6 years of age

Safety Monitoring in Paediatrics

• Neuropsychiatric symptoms: Screen at each visit for agitation, aggressive behaviour, anxiety, depression, sleep disturbances, nightmares, hallucinations, suicidal ideation

• Growth: Monitor height and weight at routine intervals

• Asthma control: Assess symptom control, rescue medication use, exacerbation frequency

• Counsel parents/caregivers: Alert to report any behavioural or mood changes immediately

Secondary Paediatric Indications (Off-label)

Indication Age Dose Duration Notes

Adenoidal hypertrophy (mild-moderate) >2 years Age-appropriate dose (4–5 mg once daily) 3–6 months trial OFF-LABEL; Specialist (ENT/Paediatric) only; Indian ENT practice; may reduce adenoid size and symptoms; evidence limited

Otitis media with effusion (adjunctive) >2 years Age-appropriate dose (4–5 mg once daily) 3 months OFF-LABEL; Specialist only; used with intranasal steroids; modest benefit in some studies

Allergic conjunctivitis (adjunctive) >6 years Age-appropriate dose Seasonal use OFF-LABEL; Limited evidence; use with topical therapy

Post-viral wheeze (recurrent) 6 months – 5 years 4 mg once daily During viral illness + 1–2 weeks after OFF-LABEL; May reduce wheeze episodes in virus-triggered wheezers; IAP practice

No dosage adjustment required.

Montelukast is primarily metabolised hepatically with negligible renal excretion of parent drug. Safe to use at standard doses in all stages of renal impairment including dialysis patients.

• Known hypersensitivity to montelukast or any excipient (including mannitol, aspartame in chewable tablets)

• NOT for acute asthma attacks or status asthmaticus (lacks bronchodilator activity)

• Severe hepatic impairment

• Phenylketonuria (chewable tablets contain aspartame)

• Neuropsychiatric events: Agitation, aggressive behaviour, anxiety, depression, disorientation, attention disturbance, dream abnormalities, hallucinations, insomnia, irritability, memory impairment, restlessness, somnambulism, suicidal thinking and behaviour, tremor — monitor closely; discontinue if symptoms emerge

• Systemic eosinophilic conditions: May unmask Churg-Strauss syndrome (eosinophilic granulomatosis with polyangiitis) particularly during corticosteroid dose reduction — monitor for vasculitic rash, worsening pulmonary symptoms, cardiac complications, neuropathy

• Aspirin/NSAID sensitivity: Not a substitute for avoiding aspirin in sensitive patients; does not completely block aspirin-induced reactions

• Psychiatric history: Use with heightened vigilance; consider alternative therapies if possible

• Reduction of oral corticosteroid dose: Taper corticosteroids gradually; do not substitute montelukast for corticosteroids abruptly

• Lactose intolerance: Some formulations contain lactose

Parameter Details

Risk Category Limited human data; animal studies show no teratogenicity; considered relatively low risk

Overall Safety May be continued if already on treatment with good asthma control prior to pregnancy

Preferred Alternatives Inhaled corticosteroids (budesonide preferred ICS in pregnancy); inhaled SABA for rescue

When May Be Used Continue if: well-controlled asthma pre-pregnancy on montelukast; alternative options not suitable; benefit outweighs theoretical risk

What to Monitor Maternal asthma control; fetal growth (poorly controlled asthma itself risks IUGR, preterm delivery)

Recommendations Do not initiate new therapy in pregnancy unless essential; if currently on montelukast with good control, may continue after shared decision-making

Parameter Details

Compatibility Likely compatible; limited human data

Milk Levels Unknown in humans; expected to be low based on pharmacokinetics

Preferred Alternatives Inhaled corticosteroids, inhaled SABA (minimal systemic absorption)

Infant Monitoring Observe for irritability, sleep disturbances, feeding difficulties

Recommendations Can be used if clinically indicated; prefer inhaled therapies when possible

Parameter Recommendation

Starting dose 10 mg once daily (same as adults)

Titration Not applicable

Special Considerations No dose adjustment for age alone; assess hepatic function before initiation

Extra Risks Increased susceptibility to neuropsychiatric effects (confusion, mood changes, sleep disturbances); monitor closely; polypharmacy interactions

Monitoring Cognitive and mood assessment at follow-up visits

Rifampicin Marked reduction in montelukast exposure (up to 40% decrease in AUC) Strong CYP3A4 inducer Monitor for reduced efficacy; consider alternative asthma therapy during rifampicin treatment

Phenobarbital Reduced montelukast levels CYP3A4 induction Monitor asthma control; may need alternative controller

Phenytoin Reduced montelukast levels CYP3A4 induction Monitor clinical response

Carbamazepine Reduced montelukast levels CYP3A4 induction Monitor for loss of efficacy

Gemfibrozil Increased montelukast exposure (4–5 fold increase in AUC) CYP2C8 inhibition Monitor for increased adverse effects; no dose adjustment typically needed but increased vigilance for neuropsychiatric symptoms

Interacting Drug Effect Recommendation

Fluconazole May modestly increase montelukast levels CYP2C9 inhibition; usually clinically insignificant; monitor

Itraconazole / Ketoconazole May slightly increase montelukast levels CYP3A4 inhibition; minimal clinical significance

Erythromycin / Clarithromycin May slightly increase montelukast levels Mild CYP3A4 inhibition; no dose adjustment needed

Prednisone / Prednisolone No pharmacokinetic interaction Can be used together; taper corticosteroids carefully if reducing

Theophylline No significant interaction Can be used together; montelukast does not affect theophylline levels

Inhaled corticosteroids No interaction Additive benefit; recommended combination

Antihistamines (cetirizine, fexofenadine, levocetirizine) No interaction Commonly used together for allergic rhinitis; additive benefit

Oral contraceptives No significant interaction No dose adjustment needed

Warfarin No clinically significant effect on INR Standard monitoring; no adjustment needed

Digoxin No interaction No monitoring required

Adults:

• Headache

• Upper respiratory tract infection

• Pharyngitis

• Cough

• Abdominal pain

• Dyspepsia

• Diarrhoea

• Fatigue

• Dizziness

• Influenza-like symptoms

• Rash (mild)

Paediatric (additional):

• Thirst

• Hyperkinesia

• Otitis media

• Fever

• Sinusitis

Adverse Effect Clinical Notes

Neuropsychiatric events Agitation, aggression, anxiety, depression, disorientation, dream abnormalities, hallucinations, insomnia, suicidal ideation and behaviour; discontinue immediately and evaluate; US FDA boxed warning

Eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome) Eosinophilia, vasculitic rash, pulmonary symptoms, peripheral neuropathy, cardiac involvement; usually emerges when corticosteroids are tapered; discontinue and refer urgently

Anaphylaxis / Angioedema Rare; discontinue immediately; emergency management

Hepatotoxicity Rare; cholestatic hepatitis, mixed hepatocellular injury reported; monitor if unexplained symptoms; discontinue if significant LFT elevation

Erythema multiforme / Stevens-Johnson syndrome Very rare; discontinue immediately; hospitalisation required

Thrombocytopenia Very rare case reports

Seizures Rare reports; caution in epilepsy

Palpitations / Peripheral oedema Rare; evaluate cardiac status

After initiation (2–4 weeks) Assess clinical response (symptom control); screen for neuropsychiatric symptoms (especially in children and adolescents)

Ongoing (every 3–6 months) Asthma control assessment (ACT/ACQ scores, symptom diary, rescue medication use, exacerbation frequency); neuropsychiatric symptom review; adherence check

Long-term Periodic review of continued need for therapy; step-down consideration if asthma well-controlled; growth monitoring in children

If neuropsychiatric symptoms emerge Immediate discontinuation; psychiatric evaluation as needed

Single-Ingredient Brands

Brand Name Manufacturer Formulations

Montair Cipla 4 mg chewable, 5 mg chewable, 10 mg tablet, 4 mg granules

Montek Sun Pharma 4 mg chewable, 5 mg chewable, 10 mg tablet, 4 mg granules

Telekast Lupin 4 mg chewable, 5 mg chewable, 10 mg tablet

Romilast Ranbaxy/Sun 10 mg tablet, 4 mg chewable, 5 mg chewable

Montemac Macleods 10 mg tablet, 5 mg chewable

Montelo Intas 10 mg tablet

Singulair MSD (originator) 4 mg chewable, 5 mg chewable, 10 mg tablet, 4 mg granules

Odimont Zydus 10 mg tablet, 5 mg chewable

Fixed-Dose Combinations (FDCs) — Common

Brand Name Combination Notes

Montemac-L Montelukast + Levocetirizine

Note: FDCs with antihistamines widely prescribed in India for allergic rhinitis; may increase sedation with levocetirizine combinations

• NLEM Status: Montelukast is included in NLEM India 2022

• DPCO: Price ceiling applicable

• Government supply: Available in some public health facilities

1. NOT a rescue medication: Reinforce to patients and caregivers that montelukast does NOT relieve acute asthma symptoms — SABA (salbutamol) remains the rescue drug; montelukast takes days to weeks for full effect

1. Evening dosing preferred: Circadian variation in leukotriene synthesis peaks at night; evening administration optimises efficacy for asthma and nocturnal symptoms

1. Steroid-sparing role: Valuable add-on to ICS in Step 3–4 asthma (GINA/Indian guidelines); particularly useful in aspirin-sensitive asthma, exercise-induced symptoms, and patients reluctant/unable to increase ICS

1. Neuropsychiatric vigilance essential: US FDA boxed warning (2020); screen for mood changes, behavioural disturbances, sleep abnormalities at EVERY visit; particularly important in children and adolescents; counsel parents/caregivers to report immediately

1. Churg-Strauss caution: Do not attribute new-onset vasculitis, worsening eosinophilia, or neuropathy to "asthma worsening" — consider EGPA especially when tapering corticosteroids; requires urgent referral

1. Oral granules administration: Mix with one spoonful of soft food only (not liquids); use within 15 minutes of mixing; do not store prepared mixture

1. FDC caution: Montelukast + levocetirizine FDCs are popular but may cause sedation; avoid evening dosing of FDC in patients reporting next-morning drowsiness; consider separate dosing timings

asthma; leukotriene-receptor-antagonist; LTRA; allergic-rhinitis; exercise-induced-bronchoconstriction; paediatric-use; neuropsychiatric-warning; steroid-sparing; NLEM-India; add-on-therapy

RxIndia v1.0 — 27 Jan 2025

• CDSCO approved prescribing information for Montelukast

• Indian Pharmacopoeia 2022

• NLEM India 2022

• API Textbook of Medicine (11th Edition) — Bronchial Asthma, Allergic Rhinitis chapters

• IAP Guidelines on Childhood Asthma (2021)

• Indian Chest Society / NCCP Guidelines on Asthma Management

• AIIMS Treatment Protocols — Allergy and Pulmonology

• GINA 2023 (supportive reference, adapted to Indian context)

• US FDA Drug Safety Communication — Montelukast Neuropsychiatric Events (March 2020)

• Indian ENT specialist practice guidelines (for adenoidal hypertrophy off-label use)

• Goodman & Gilman's The Pharmacological Basis of Therapeutics (14th Edition)

• Harrison's Principles of Internal Medicine (21st Edition)