Lecrolyn Sine (Sodium Cromoglicate)

Lecrolyn Sine, a mast cell stabilizer, is used to manage ocular allergic conditions by preventing release of inflammatory mediators.

• Allergic conjunctivitis: reduces redness, itching and tearing associated with seasonal or perennial eye allergy.
• Vernal keratoconjunctivitis: diminishes intense inflammation and photophobia in this chronic allergic disease.
• Ocular allergy: provides symptomatic relief for general allergic inflammation of the conjunctiva.

• Sodium cromoglicate stabilizes mast cells by inhibiting calcium‑dependent degranulation, which blocks the release of histamine, leukotrienes and other inflammatory mediators from ocular tissues. By maintaining the integrity of the cell membrane, it limits the cascade that leads to allergic inflammation in the conjunctiva, providing symptomatic relief without directly antagonizing histamine receptors. The effect is localized to the ocular surface, and systemic absorption is minimal, contributing to its safety profile.

Topical ocular administration of sodium cromoglicate may be associated with local and, rarely, systemic adverse reactions.

Common Side Effects

• Transient ocular burning or stinging on instillation, usually resolving within minutes.
• Mild conjunctival hyperemia presenting as slight redness without pain.
• Temporary blurred vision that clears shortly after the drop is absorbed.
• Tear film instability leading to brief sensation of dryness.

Serious or Rare Side Effects

• Allergic contact dermatitis of the eyelid or peri‑ocular skin, requiring discontinuation.
• Severe ocular irritation persisting beyond 24 hours and not improving with standard measures.
• Corneal epithelial defect or ulceration that may need ophthalmic evaluation.
• Vision loss, an extremely rare event reported in isolated cases.

When prescribing Lecrolyn Sine, clinicians should consider several precautionary measures to ensure safe use.

• Contraindication: known hypersensitivity to sodium cromoglicate or any formulation component.
• Caution: use with care in patients with pre‑existing ocular surface disease such as severe dry eye.
• Monitoring: advise patients to report persistent burning, swelling, or vision changes.
• Pregnancy: safety has not been established; use only if potential benefit outweighs risk.
• Pediatric use: limited data; prescribe under specialist supervision.
• Store at room temperature: keep in original container, protect from light and moisture.

Sodium cromoglicate has a low potential for drug‑drug interactions, but certain combinations warrant attention.

Major Interactions (Avoid)

• Concurrent use with ocular prostaglandin analogues may reduce efficacy of cromoglicate.
• Co‑administration with preservative‑containing eye drops can increase risk of ocular irritation.

Moderate Interactions (Monitor Closely)

• Use with other mast‑cell stabilizers may increase local side‑effects without added benefit.
• Combination with topical corticosteroids may enhance anti‑inflammatory effect; monitor intra‑ocular pressure.
• Systemic antihistamines may diminish patient perception of ocular symptoms; assess response.