Levocetirizin Glenmark (Levocetirizine Dihydrochloride)

Levocetirizine is a second‑generation antihistamine that reduces histamine‑mediated allergic responses.

• Allergic rhinitis: relieves nasal congestion, sneezing, itching and rhinorrhea associated with seasonal or perennial allergens.
• Chronic idiopathic urticaria: decreases the number and intensity of hives and associated pruritus.
• Seasonal allergic rhinitis: mitigates nasal symptoms triggered by pollen and other seasonal allergens.

• Levocetirizine selectively blocks peripheral H1 histamine receptors, preventing histamine from binding to mast cells and basophils. This antagonism inhibits the cascade of allergic inflammation, reducing vascular permeability, edema, and sensory nerve activation that cause typical allergy symptoms.

Levocetirine may be associated with a range of adverse reactions, most of which are mild and transient.

Common Side Effects

• Drowsiness: mild to moderate sedation, especially at initiation.
• Headache: transient tension‑type headaches.
• Dry mouth: reduced salivation leading to mild oral dryness.
• Nausea: occasional stomach upset.
• Taste alteration: temporary changes in flavor perception.

Serious or Rare Side Effects

• Angioedema: swelling of lips, tongue or face requiring immediate medical attention.
• Severe skin reactions: such as Stevens‑Johnson syndrome or toxic epidermal necrolysis.
• Anaphylaxis: rare systemic allergic reaction with respiratory compromise.
• Hepatic enzyme elevation: abnormal liver function tests.
• Hematologic abnormalities: rare blood dyscrasias like neutropenia.

Before initiating therapy, consider the following safety measures.

• Pregnancy: consult a healthcare professional to weigh potential risks and benefits.
• Breastfeeding: evaluate infant exposure and discuss with a clinician.
• Renal impairment: dose adjustment may be necessary in patients with reduced kidney function.
• Elderly patients: monitor for increased sedation and falls.
• Driving or operating machinery: avoid if experiencing drowsiness.
• Store at room temperature: keep in the original container, protect from moisture and light.

Levocetirizine can interact with other medicines; awareness helps prevent adverse outcomes.

Major Interactions (Avoid)

• Alcohol: additive central nervous system depression leading to excessive drowsiness.
• Strong CYP3A4 inhibitors (e.g., ketoconazole, erythromycin): may increase levocetirizine plasma concentrations.
• Concomitant antihistamines: risk of cumulative sedation.

Moderate Interactions (Monitor Closely)

• Theophylline: possible increase in theophylline levels, requiring monitoring.
• CNS depressants (e.g., benzodiazepines, opioids): may enhance sedative effects.
• Ritonavir: may raise levocetirizine exposure, warranting observation.