Levocetirizine Sandoz (Levocetirizine Dihydrochloride)

Levocetirizine is an antihistamine that targets H1‑mediated allergic pathways, providing relief in several common allergic conditions.

• Allergic rhinitis: alleviates nasal congestion, sneezing, itching and watery discharge caused by seasonal or perennial allergens.
• Chronic idiopathic urticaria: reduces the frequency and intensity of hives and associated pruritus in patients with persistent urticaria.
• Seasonal allergic conjunctivitis: diminishes eye itching, redness and tearing linked to pollen or other airborne allergens.

• Levocetirizine is the active R‑enantiomer of cetirizine and acts as a highly selective antagonist of peripheral H1 histamine receptors. By binding to these receptors on mast cells, basophils and sensory nerves, it blocks the action of released histamine, thereby preventing the cascade that leads to vasodilation, increased vascular permeability, and sensory nerve stimulation responsible for allergic symptoms.

Levocetirizine is generally well tolerated, but like all medicines it may cause adverse reactions.

Common Side Effects

• Drowsiness: mild sleepiness that may affect alertness.
• Fatigue: general feeling of tiredness.
• Dry mouth: reduced salivation.
• Headache: mild to moderate head pain.
• Nausea: upset stomach or feeling of queasiness.
• Altered taste: temporary metallic or bitter taste.

Serious or Rare Side Effects

• Anaphylaxis: severe, potentially life‑threatening allergic reaction.
• Angioedema: swelling of face, lips, tongue or throat.
• Stevens‑Johnson syndrome: rare severe skin eruption.
• Cardiac arrhythmia: uncommon irregular heartbeat.

Before prescribing Levocetirizine, clinicians should consider several precautionary measures to ensure safe use.

• Pregnancy: evaluate risk‑benefit and consult obstetric guidance before use.
• Lactation: monitor infant for possible sedation; weigh benefits against potential exposure.
• Renal impairment: dose may require adjustment in patients with reduced kidney function.
• Elderly patients: observe for increased sensitivity to drowsiness or sedation.
• Concomitant CNS depressants: avoid additive sedation when combined with alcohol or other sedatives.
• Store at room temperature: keep in original packaging, protect from moisture and excessive heat.

Levocetirizine may interact with other medicines, altering its plasma concentration or enhancing pharmacodynamic effects.

Major Interactions (Avoid)

• Ketoconazole: strong CYP3A4 inhibition can increase levocetirizine levels.
• Ritonavir: potent CYP3A4 inhibitor may raise drug exposure.
• Other sedating antihistamines: combined use can cause excessive CNS depression.

Moderate Interactions (Monitor Closely)

• Alcohol: may potentiate drowsiness and impair coordination.
• Central nervous system depressants (e.g., benzodiazepines): monitor for enhanced sedation.
• Theophylline: may increase levocetirizine clearance, reducing efficacy.