Levocabastin (Levocabastine Hydrochloride)

Levocabastine is used to treat allergic conditions of the nasal passages by antagonizing histamine activity.

• Allergic rhinitis: reduces nasal congestion, itching, sneezing and rhinorrhea.
• Seasonal allergic nasal symptoms: alleviates pollen‑induced nasal irritation and discharge.
• Non‑seasonal allergic rhinitis: provides symptom relief for year‑round allergen exposure.

• Levocabastine acts as a selective competitive antagonist at histamine H1 receptors located on nasal mucosal cells. By binding to these receptors, it prevents histamine‑mediated vasodilation, increased vascular permeability, and sensory nerve activation, which are responsible for the classic symptoms of allergic rhinitis such as congestion, itching, sneezing, and rhinorrhea. The blockade is reversible and confined to the nasal epithelium, allowing rapid onset of relief with minimal systemic exposure.

Levocabastine nasal spray may cause local and systemic adverse reactions, most of which are mild and transient.

Common Side Effects

• Nasal irritation or burning sensation.
• Bitter or unpleasant taste.
• Headache.
• Transient drowsiness.

Serious or Rare Side Effects

• Epistaxis (nosebleed).
• Severe hypersensitivity reactions, including rash or angioedema.
• Nasal ulceration or crusting.
• Anaphylactic shock (rare).

When using Levocabastine nasal spray, certain precautions should be observed to ensure safety and effectiveness.

• Hypersensitivity: avoid use in patients with known allergy to levocabastine or any formulation components.
• Age considerations: follow prescriber guidance for pediatric use, especially in children under six years.
• Concomitant nasal products: do not use simultaneously with other intranasal medications without medical advice.
• Pregnancy and lactation: consult a healthcare professional before use, as safety data are limited.
• Driving or operating machinery: caution if drowsiness occurs.
• Store at room temperature: keep in original container, protect from moisture and direct sunlight.

Levocabastine may interact with other medicines, altering its efficacy or increasing the risk of adverse effects.

Major Interactions (Avoid)

• Other H1‑antihistamines: additive sedation and reduced therapeutic benefit.
• Monoamine oxidase inhibitors (MAOIs): potential for exaggerated antihistaminic effects.
• Alcohol: increased drowsiness and impaired coordination.

Moderate Interactions (Monitor Closely)

• Nasal decongestants (e.g., oxymetazoline): risk of nasal irritation when combined.
• CYP3A4 inhibitors: may modestly increase systemic exposure.
• Central nervous system depressants: monitor for enhanced sedation.