Prescription requiredAnti-allergic (antihistamine + leukotriene receptor antagonist)

Allegra M Tab — Side Effects & Warnings

Known side effects of Allegra M Tab include Headache, dizziness, drowsiness (rare), nausea, abdominal pain, dry mouth, fatigue, diarrhea, sore throat. Not everyone experiences these side effects.

Medically reviewed by Dr. Balaji Krishnan, MBBS · Updated June 2026

Common Side Effects

Headache
dizziness
drowsiness (rare)
nausea
abdominal pain
dry mouth
fatigue
diarrhea
sore throat

This is not an exhaustive list. Consult your doctor if you notice any unusual symptoms.

Important Warnings

Use with caution in kidney impairment (fexofenadine) and in patients with history of neuropsychiatric symptoms (montelukast). Montelukast has been associated with mood/behavior changes (agitation, anxiety, sleep disturbance, depression, suicidal thoughts); stop and seek medical advice if such symptoms occur. Not for acute asthma attacks. May cause dizziness in some patients—use caution while driving. Inform doctor about all medicines and allergies.

Drug Interactions

Allegra M Tab may interact with the following:

Fruit juices (apple/orange/grapefruit) may reduce fexofenadine absorption; antacids containing aluminium/magnesium may reduce absorption (separate by 2 hours); erythromycin/ketoconazole may increase fexofenadine levels; rifampicin may reduce montelukast levels; gemfibrozil may increase montelukast exposure

Always tell your doctor about all medicines you are taking, including over-the-counter drugs and supplements.

Pregnancy Safety

Consult doctor

Alcohol Interaction

Use with caution

Habit Forming

Storage

Store at room temperature (below 25°C), protected from moisture and light. Keep in original blister pack and out of reach of children.

Allegra M Tab — Safety Summary

Composition: Fexofenadine hydrochloride 120 mg + Montelukast 10 mg
Prescription: Required (Rx)
Pregnancy: Consult doctor
Alcohol: Use with caution
Habit forming: No

Allegra M Tab — Safety FAQs

What should I do if I experience side effects?

Mild side effects often resolve on their own. If side effects are severe or persistent, stop the medicine and consult your doctor immediately.

Are all listed side effects common?

No. Some side effects are common while others are rare. Not everyone experiences side effects. Consult your doctor if you are concerned.

Can I take this medicine with other drugs?

Some medicines interact with each other. Always inform your doctor about all medicines you are currently taking.

When should I seek emergency help?

Seek immediate medical attention if you experience severe allergic reactions (difficulty breathing, swelling of face/throat), chest pain, or any life-threatening symptoms.

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Safety disclaimer

This information is for educational purposes only and is not a substitute for professional medical advice. If you experience severe side effects, seek medical attention immediately.