Molecule

Drug Groups

approved

Description

Pemirolast potassium is a slightly yellow powder that is soluble in water. It is a mast cell stabilizer that acts as an antiallergic agent. As an ophthalmic aqueous sterile solution, pemirolast is used for the prevention of itching of the eyes caused by allergies such as hay fever, and allergic conjunctivitis. Pemirolast is potentially useful for prophylaxis of pulmonary hypersensitivity reactions to drugs such as paclitaxel.

Indication

For the prevention of itching of the eyes caused by allergies such as hay fever, and allergic conjunctivitis

Pharmacology

Pemirolast is used for the prophylactic treatment of itching of the eye associated with allergic conjunctivitis. Pemirolast potassium is a mast cell stabilizer that inhibits the in vivo Type I immediate hypersensitivity reaction. Pemirolast inhibits the antigen-induced release of inflammatory mediators (e.g., histamine, leukotriene C4, D4, E4) from human mast cells. Allergic reactions lead to cell-degranulation and the release of histamine (and other chemical mediators) from the mast cell or basophil. Once released, histamine can react with local or widespread tissues through histamine receptors. Histamine, acting on H₁-receptors, produces pruritis and vasodilatation (allowing blood fluids to enter the area to cause swelling). Pemirolast is a histamine H1 antagonist. It competes with histamine for the normal H₁-receptor sites on effector cells of blood vessels to provide effective, temporary relief of watery and itchy eyes.

Affected Organisms

Biotransformation

Hepatic (Ophthalmic)

Half Life

4.5 hours (Ophthalmic)

Elimination

Following topical administration, about 10-15% of the dose was excreted unchanged in the urine.

References

External Links