Sodium Cromoglycate (SCG) is a mast cell stabilizer used primarily as a topical ophthalmic solution for the management of allergic conjunctivitis. It acts prophylactically to inhibit the degranulation of sensitized mast cells, thereby preventing the release of inflammatory mediators like histamine, leukotrienes, and prostaglandins. It is a first-line prophylactic agent for allergic eye conditions and is known for its excellent safety profile.
Adult: One to two drops in each affected eye, 4 to 6 times daily at regular intervals. Frequency may be increased during periods of high allergen exposure.
Note: 1. Wash hands before use. 2. Tilt head back, pull lower eyelid down to form a pouch. 3. Instill the prescribed number of drops without touching the dropper tip to the eye or any surface. 4. Close eyes gently and apply pressure to the inner corner of the eye (nasolacrimal occlusion) for 1-2 minutes to minimize systemic absorption. 5. Wait at least 5-10 minutes before instilling any other eye medication. 6. Do not wear soft contact lenses during treatment unless advised by a doctor.
Sodium Cromoglycate inhibits the degranulation of sensitized mast cells that occurs after exposure to specific antigens. It blocks the inward flux of calcium ions (Ca2+) across the mast cell membrane, a critical step for the fusion of secretory granules with the plasma membrane. This prevents the release of preformed mediators like histamine and the synthesis of newly formed mediators such as leukotrienes (SRS-A), prostaglandins, and platelet-activating factor (PAF).
Pregnancy: Pregnancy Category B (US FDA). Animal studies have shown no risk, but adequate and well-controlled studies in pregnant women are lacking. Use only if clearly needed and potential benefit justifies potential risk to the fetus.
Driving: May cause transient blurred vision immediately after instillation. Patients should not drive or operate machinery until vision clears.
| Other topical ophthalmic medications | Physical incompatibility if mixed. Instillation of multiple drops can wash out the previous drug. | Moderate |
| Topical corticosteroids (e.g., Loteprednol) | SCG can be used concomitantly as a prophylactic agent, allowing for potential reduction in steroid use. No direct pharmacokinetic interaction. | Minor |