Introduction
Epinastine is used for the prevention of itching associated with allergic conjunctivitis. It has a multi-action effect that inhibits the allergic response in 3 ways: 1. stabilizes mast cells by preventing mast cell degranulation to control the allergic response, 2. prevents histamine binding to both the H1- and H2-receptors to stop itching and provide lasting protection, and 3. prevents the release of proinflammatory chemical mediators from the blood vessel to halt progression of the allergic response.
Uses
Epinastine is an H1 receptor antagonist used to prevent itching in allergic conjunctivitis.
For the prevention of itching associated with allergic conjunctivitis.
Associated Conditions
Pharmacodynamics
Epinastine is an antihistamine and an inhibitor of histamine release from the mast cell for topical administration to the eyes. Epinastine is indicated for the prevention of itching associated with allergic conjunctivitis. Epinastine is a topically active, direct H1-receptor antagonist and an inhibitor of the release of histamine from the mast cell. Epinastine is selective for the histamine H1-receptor and has affinity for the histamine H2 receptor. Epinastine also possesses affinity for the a1-, a2-, and 5-HT2 -receptors. Epinastine does not penetrate the blood/brain barrier and, therefore, is not expected to induce side effects of the central nervous system.
Mechanism of Action
Epinastine has a multiaction effect that inhibits the allergic response in 3 ways: 1. stabilizes mast cells by preventing mast cell degranulation to control the allergic response, 2. prevents histamine binding to both the H1- and H2-receptors to stop itching and provide lasting protection, and 3. prevents the release of proinflammatory chemical mediators from the blood vessel to halt progression of the allergic response.
Absorption
The absolute bioavailability of epinastine is about 40%.
Protein Binding
64%
Route of Elimination
Epinastine is mainly excreted unchanged. The renal elimination is mainly via active tubular secretion.
Half Life
12 hours
Clearance
- 56 L/hr [patients with allergic conjunctivitis receiving one drop of ELESTAT® ophthalmic solution in each eye twice daily for seven days]
Food Interactions
No interactions found.
