Action And Clinical Pharmacology: Emedastine is a potent, selective, and topically effective histamine H1 antagonist with a rapid onset of action. In vitro and in vivo examinations of emedastine’s affinity for histamine receptors (H1, H2 and H3) demonstrate 10 000-fold selectivity for the H1 histamine receptor and concentration-dependent inhibition of histamine-stimulated vascular permeability in the conjunctiva following topical ocular administration. Emedastine is devoid of effects on adrenergic, dopaminergic and serotonin receptors.
As with other topically administered drugs, emedastine is absorbed systemically. In a study involving 10 normal volunteers dosed bilaterally twice daily for 15 days with emedastine ophthalmic solution 0.05%, plasma concentrations of the parent compound were generally below the quantitation limit of the assay.
Indications And Clinical Uses: For the relief within minutes of the signs and symptoms of allergic conjunctivitis.
Contra-Indications: Hypersensitivity to any component of this product.
Manufacturers’ Warnings In Clinical States: For topical use only. Not for injection. Patients should be instructed not to instill emedastine while wearing contact lenses, but to wait 10 minutes after instillation before inserting contact lenses.
Precautions: Information to be Provided to the Patient: To prevent contaminating the dropper tip and solution, care should be taken not to touch the eyelids or surrounding areas with the dropper tip of the bottle. Keep the bottle tightly closed when not in use.
Carcinogenesis, Mutagenesis, Impairment of Fertility: Emedastine demonstrated no carcinogenicity effects in lifetime studies in mice and rats at dietary doses up to 35 000 and 11 000 times the maximum recommended ocular human dose level, respectively. Higher dose levels were not tested. Emedastine was determined to be nonmutagenic in an in vitro bacterial reverse mutation (Ames) test, an in vitro modification of the Ames test, an in vitro mammalian chromosome aberration test, an in vitro mammalian forward mutation test, an in vitro mammalian DNA repair synthesis test, an in vivo mammalian sister chromatid exchange test and an in vivo mouse micronucleus test. There was no evidence of impaired fertility or reproductive capacity in rats at 6 200 times the maximum recommended ocular human use level.
Pregnancy: Teratology and peri- and postnatal studies have been conducted with emedastine in rats and rabbits. At 6 200 times the maximum recommended ocular human use level, emedastine was shown not to be teratogenic in rats and rabbits and no effects on peri-/postnatal development were observed in rats. There are, however, no adequate and well-controlled studies in pregnant women. Because animal studies are not always predictive of human responses, this drug should be used in pregnant women only if the potential benefit to the mother justifies the potential risk to the embryo or fetus.
Lactation: Emedastine has been identified in breast milk in rats following oral administration. It is not known whether topical ocular administration could result in sufficient systemic absorption to produce detectable quantities in breast milk. Nevertheless, caution should be exercised when emedastine is administered to a nursing mother.
Children: Safety and effectiveness in pediatric patients between the ages of 3 and 16 have been established.
Adverse Reactions: In clinical studies of emedastine, mild transient burning or stinging was reported at an incidence of 1.4%. All other ocular and nonocular adverse reactions related to therapy were reported at an incidence equal to or less than 1%.
Ocular: pruritus, hyperemia, dry eye, corneal staining, eye fatigue, foreign body sensation, blurred vision, tearing, infiltrate, irritation.
Nonocular: headache, asthenia, abnormal dreams, dermatitis, taste perversion.
Symptoms And Treatment Of Overdose: Symptoms and Treatment: A topical overdosage may be flushed from the eye(s) with warm tap water.
Dosage: The recommended dose is 1 to 2 drops in each affected eye 4 times daily.
Availability And Storage: Each mL of sterile ophthalmic solution contains: emedastine difumarate equivalent to emedastine 0.5 mg (0.05%) and benzalkonium chloride 0.01% as preservative. Nonmedicinal ingredients: hydrochloric acid and/or sodium hydroxide, hydroxypropyl methylcellulose, purified water, sodium chloride and tromethamine. Drop-Tainer dispensers of 5 mL. Store at 4 to 30°C. Protect from light.
EMADINE® Alcon Emedastine Difumarate Antiallergy Agent