Levocetirizina Pharma Combix (Levocetirizine Dihydrochloride)

Levocetirizine is a selective H1‑receptor antagonist used to manage allergic disorders.

• Allergic rhinitis: reduces nasal congestion, sneezing, itching and rhinorrhea.
• Chronic idiopathic urticaria: diminishes the frequency and severity of hives and associated itching.
• Seasonal allergic rhinitis: provides symptom relief during pollen seasons.

• Levocetirizine acts as a highly selective antagonist of peripheral histamine H1 receptors. By binding to these receptors, it blocks the action of endogenous histamine released during allergic reactions, thereby preventing the cascade that leads to vasodilation, increased vascular permeability, and sensory nerve stimulation responsible for typical allergy symptoms.

Levocetirizine is generally well tolerated, but adverse reactions can occur.

Common Side Effects

• Drowsiness: mild to moderate sleepiness, especially after the first dose.
• Headache: transient tension‑type headache.
• Dry mouth: reduced salivation causing mild discomfort.
• Fatigue: feeling of reduced energy.
• Nausea: occasional upset stomach.
• Abdominal discomfort: mild stomach pain or cramps.

Serious or Rare Side Effects

• Angioedema: swelling of face, lips or tongue requiring urgent care.
• Anaphylaxis: severe allergic reaction with respiratory distress.
• Stevens‑Johnson syndrome: rare severe skin eruption.
• Tachycardia: abnormal rapid heart rate.
• Hepatic injury: elevated liver enzymes.
• Blood dyscrasias: neutropenia or thrombocytopenia.

Before initiating therapy, clinicians should consider several safety aspects.

• Renal function assessment: dose adjustment may be needed in impaired renal clearance.
• Elderly patients: monitor for increased sedation or anticholinergic effects.
• Driving and machinery: advise caution if drowsiness occurs.
• Concomitant CNS depressants: avoid or monitor for additive sedation.
• Hypersensitivity history: screen for prior reactions to antihistamines.
• Store at ambient temperature: keep in the original pack, protect from moisture.

Levocetirizine may interact with other medicines, requiring attention to avoid adverse outcomes.

Major Interactions (Avoid)

• Other antihistamines: additive H1 blockade can increase sedation.
• Alcohol or CNS depressants: may potentiate drowsiness and impair coordination.
• Monoamine oxidase inhibitors (MAOIs): rare reports of enhanced antihistaminic effects.

Moderate Interactions (Monitor Closely)

• Strong CYP3A4 inhibitors (e.g., ketoconazole): may modestly increase plasma levels.
• Theophylline: potential for altered theophylline metabolism.
• QT‑prolonging agents: monitor cardiac rhythm if combined with drugs that affect cardiac repolarisation.