Not Scheduled (Over-the-Counter)

Oral

• Tablets: 60 mg, 120 mg, 180 mg

• Oral suspension: 30 mg/5 mL

Fixed-Dose Combinations Available:

• Fexofenadine 120 mg + Montelukast 10 mg tablets

• Fexofenadine 180 mg + Montelukast 10 mg tablets

INDICATIONS + DOSING — FOR CLINICIAN USE ONLY

Primary Indications (Approved / Standard in India)

1. Allergic Rhinitis (Seasonal and Perennial) — Adults

Parameter Recommendation

Starting dose 120 mg orally once daily

Titration Not applicable

Usual maintenance dose 120 mg once daily

Maximum dose 180 mg once daily

Clinical Notes:

• Once-daily dosing provides 24-hour symptom relief

• Non-sedating — suitable for patients requiring alertness (drivers, machine operators)

• Take with water; avoid fruit juices (apple, orange, grapefruit) which reduce absorption

1. Chronic Idiopathic Urticaria — Adults

Parameter Recommendation

Starting dose 180 mg orally once daily

Titration Not applicable

Usual maintenance dose 180 mg once daily

Maximum dose 180 mg once daily (standard dosing); up to 360 mg/day off-label in refractory cases

Clinical Notes:

• Administer at same time daily for consistent symptom control

• Assess response after 2 weeks; consider alternative if inadequate response

• Avoid administration within 2 hours of antacids containing aluminium or magnesium

Secondary Indications — Adults (Off-label)

Indication Dose Duration Notes

Refractory Chronic Urticaria (Up-dosing) 180 mg twice daily (360 mg/day) Response-guided OFF-LABEL • Specialist only • European/International guidelines support up-dosing second-generation antihistamines up to 4× standard dose • Indian dermatology practice

PAEDIATRIC DOSING (Specialist Only)

Primary Indications (Approved / Standard in India)

1. Allergic Rhinitis / Chronic Idiopathic Urticaria

Age-Based Dosing:

6 months to <2 years Oral suspension 15 mg (2.5 mL) twice daily 30 mg/day

2 to <6 years Oral suspension 30 mg (5 mL) twice daily 60 mg/day

6 to <12 years Oral suspension or tablets 30 mg twice daily 60 mg/day

≥12 years Tablets Adult dosing (120–180 mg once daily) 180 mg/day

Standardised Format:

Parameter Children 6 months to <12 years Children ≥12 years

Starting dose As per age-based table above 120 mg once daily

Titration Not applicable Not applicable

Usual maintenance dose As per age-based table above 120–180 mg once daily

Maximum dose 60 mg/day 180 mg/day

Clinical Notes:

• Oral suspension preferred for children <6 years or those unable to swallow tablets

• Shake suspension well before use

• Administer before meals for optimal absorption

• Non-sedating profile advantageous for school-going children

Safety Monitoring:

• Assess symptom control

• Monitor for drowsiness (uncommon but possible)

• No routine laboratory monitoring required

Secondary Indications — Paediatric (Off-label)

Not applicable — No established off-label paediatric uses in Indian practice.

Age Restrictions:

• Not recommended in infants <6 months except under specialist supervision

• Limited data in infants; use only when benefit clearly outweighs risk

Haemodialysis:

• Fexofenadine is not significantly removed by haemodialysis (high protein binding, large volume of distribution)

• No supplemental dose required post-dialysis

• Administer at any time relative to dialysis session

Notes:

• Fexofenadine is primarily excreted unchanged in faeces (~80%) and urine (~11%)

• Reduced renal clearance leads to increased plasma concentrations

• Monitor for CNS effects (drowsiness, dizziness) at reduced doses

Note: Fexofenadine undergoes minimal hepatic metabolism — primarily excreted unchanged. Hepatic impairment has less impact on pharmacokinetics compared to renal impairment.

• Known hypersensitivity to fexofenadine or any component of formulation

• Known hypersensitivity to terfenadine (fexofenadine is active metabolite of terfenadine)

• Renal impairment — dose reduction required to prevent accumulation

• Concurrent administration with fruit juices (apple, orange, grapefruit) — significantly reduces bioavailability; advise patients to take with water only

• Concurrent aluminium/magnesium-containing antacids — reduces absorption; separate administration by at least 2 hours

• Elderly patients — more likely to have reduced renal function; assess before dosing

• Patients on P-glycoprotein inhibitors (erythromycin, ketoconazole) — may increase fexofenadine levels

Parameter Information

Risk Category Limited human data; animal studies show no teratogenicity

Overall Safety Use only if clearly needed; weigh benefit against potential risk

Preferred Alternatives Loratadine or cetirizine (more safety data in pregnancy); chlorpheniramine if sedation acceptable

When May Be Used When antihistamine therapy is essential and preferred alternatives not suitable

Monitoring No specific fetal monitoring required; standard antenatal care

Parameter Information

Compatibility Likely compatible with breastfeeding

Expected Milk Levels Low (minimal excretion expected based on pharmacokinetics)

Preferred Alternatives Loratadine, cetirizine (more lactation safety data available)

Decision May use if clearly indicated; observe infant

Infant Monitoring Sedation (unlikely), irritability, feeding difficulties

Parameter Recommendation

Starting dose 60 mg once daily

Titration Increase to 120 mg once daily if tolerated and needed

Special considerations Assess renal function before dosing — age-related decline common

Extra monitoring Monitor for drowsiness, dizziness, dry mouth (though less common than with first-generation antihistamines)

Risk factors Polypharmacy; concurrent anticholinergic medications may have additive effects

Interacting Drug Effect & Mechanism Management

Fruit juices (apple, orange, grapefruit) Reduce fexofenadine bioavailability by 30–40% (OATP transporter inhibition in GI tract) Avoid fruit juices within 4 hours of fexofenadine dose; take with water only

Aluminium/Magnesium-containing antacids Reduce fexofenadine absorption by ~40% Separate administration by at least 2 hours

Erythromycin Increases fexofenadine plasma levels by 80–100% (P-glycoprotein inhibition) Usually well tolerated; monitor for increased adverse effects

Ketoconazole Increases fexofenadine plasma levels by 130–160% (P-glycoprotein inhibition) Usually well tolerated; monitor for increased adverse effects

Interacting Drug Effect Management

Rifampicin May reduce fexofenadine efficacy (P-glycoprotein induction) Monitor symptom control; may need alternative antihistamine

Verapamil May increase fexofenadine levels (P-glycoprotein inhibition) Monitor for adverse effects

Anticholinergic agents Potential additive dry mouth, urinary retention Monitor especially in elderly

CNS depressants (sedatives, alcohol) Theoretical additive CNS effects (though fexofenadine is minimally sedating) Advise caution in sensitive individuals

• Headache

• Drowsiness (less common than first-generation antihistamines but may occur)

• Dizziness

• Nausea

• Dry mouth

• Fatigue

• Dysmenorrhoea (reported in clinical trials)

Adverse Effect Clinical Action

Hypersensitivity reaction / Anaphylaxis (rare) Immediate discontinuation; emergency management

QT prolongation (very rare — unlike terfenadine, fexofenadine has minimal cardiac effect) Discontinue if ECG changes noted; cardiology review

Severe skin reactions (rare) Discontinue; dermatology referral

Note: Fexofenadine has an excellent cardiac safety profile compared to terfenadine (its parent compound) and does not significantly prolong QT interval at therapeutic or supratherapeutic doses.

After initiation Assess symptom control at 2 weeks; monitor for adverse effects

Long-term Periodic renal function in elderly or renal-impaired patients on chronic therapy; reassess need for continued treatment periodically

Single-Agent Formulations:

• Allegra (Sanofi)

• Fexova (Sun Pharma)

• Fexigra (Lupin)

• Histafree (Mankind)

• Allercet-F (Micro Labs)

• Fexofen (Cipla)

• Fexo (Dr. Reddy's)

Fixed-Dose Combinations (with Montelukast):

• Allegra-M (Sanofi)

• Fexova-M (Sun Pharma)

• Montair-FX (Cipla)

• Montek-FX (Sun Pharma)

Note: Not included in NLEM 2022; prices vary by brand. Available over-the-counter at pharmacies.

• Non-sedating advantage — fexofenadine is the least sedating among commonly used second-generation antihistamines; preferred for patients requiring alertness (drivers, students, professionals)

• Fruit juice interaction is clinically significant — counsel all patients to take fexofenadine with water only; apple, orange, and grapefruit juice can reduce absorption by up to 40%

• Dose reduction essential in renal impairment — unlike cetirizine and loratadine, fexofenadine requires dose adjustment in CrCl <60 mL/min

• Once-daily dosing improves compliance — compared to twice-daily alternatives; 120 mg for allergic rhinitis, 180 mg for urticaria

• Excellent cardiac safety — no QT prolongation concerns unlike its parent compound terfenadine; safe in patients with cardiac history

• Up-dosing in refractory urticaria — specialist dermatologists may use up to 4× standard dose (off-label) in chronic urticaria unresponsive to standard dosing

Fexofenadine; antihistamine; second-generation; H1-blocker; allergic rhinitis; chronic urticaria; non-sedating; renal-adjust; paediatric-safe; OTC; pregnancy-caution

RxIndia v1.0 — 05 Jan 2025

• CDSCO Approved Drug Formulations Database

• Indian Pharmacopoeia 2022

• National Formulary of India 2021

• API Textbook of Medicine, 11th Edition

• IAP Drug Formulary (Paediatric dosing)

• AIIMS Drug Formulary

• WHO Model List of Essential Medicines for Children (supportive)

• Goodman & Gilman's The Pharmacological Basis of Therapeutics

• Manufacturer Product Inserts — Sanofi (Allegra), Sun Pharma (Fexova)