Ketotifen is a cycloheptathiophene blocker of histamine H1 receptors and release of inflammatory mediators. It has been proposed for the treatment of asthma, rhinitis, skin allergies, and anaphylaxis. Ketotifen was developed in 1970 by Sandoz Pharmaceuticals of Switzerland. It is a benzocycloheptathiophene derivative and was initially marketed as an inhibitor of anaphylaxis. The pharmacodynamic properties of ketotifen are many, because it is an inhibitor of the release and/or activity of mast cell and basophil mediators, including histamine, neutrophil, and eosinophil chemotactic factors, arachidonic acid metabolites, prostaglandins, and leukotrienes. Properties of ketotifen which may contribute to its antiallergic activity and its ability to affect the underlying pathology of asthma include inhibition of the development of airway hyper-reactivity associated with activation of platelets by PAF (Platelet Activating Factor), inhibition of PAF-induced accumulation of eosinophils and platelets in the airways, suppression of the priming of eosinophils by human recombinant cytokines and antagonism of bronchoconstriction due to leukotrienes. Ketotifen is marketed under many brand names worldwide. Ketotifen inhibits the release of mediators from mast cells involved in hypersensitivity reactions. Decreased chemotaxis and activation of eosinophils have also been demonstrated. Ketotifen also inhibits cAMP phosphodiesterase.

Olopatadine is an antihistamine (as well as anticholinergic and mast cell stabilizer) used to treat itching associated with allergic conjunctivitis (eye allergies). Olopatadine is a selective histamine H1 antagonist that binds to the histamine H1 receptor. This blocks the action of endogenous histamine, which subsequently leads to temporary relief of the negative symptoms brought on by histamine. Olopatadine is devoid of effects on alpha-adrenergic, dopamine and muscarinic type 1 and 2 receptors. Some known side effects include a headache (7% of occurrence), eye burning and/or stinging (5%), blurred vision, dry eyes, foreign body sensation, hyperemia, keratitis, eyelid edema, pruritus, asthenia, sore throat (pharyngitis), rhinitis, sinusitis, and taste perversion.

Emedastine is an antihistaminic agent, which was approved by FDA for the treatment of allergic conjunctivitis (Emadine brand name). The drug acts selectively on H1 receptors with lower affinity to H2 and H3 subtypes. Emedastine has a relatively unfavorable CNS effect profile. A small percentage of patients reported somnolence as an adverse effect after administration.

Ketotifen is a cycloheptathiophene blocker of histamine H1 receptors and release of inflammatory mediators. It has been proposed for the treatment of asthma, rhinitis, skin allergies, and anaphylaxis. Ketotifen was developed in 1970 by Sandoz Pharmaceuticals of Switzerland. It is a benzocycloheptathiophene derivative and was initially marketed as an inhibitor of anaphylaxis. The pharmacodynamic properties of ketotifen are many, because it is an inhibitor of the release and/or activity of mast cell and basophil mediators, including histamine, neutrophil, and eosinophil chemotactic factors, arachidonic acid metabolites, prostaglandins, and leukotrienes. Properties of ketotifen which may contribute to its antiallergic activity and its ability to affect the underlying pathology of asthma include inhibition of the development of airway hyper-reactivity associated with activation of platelets by PAF (Platelet Activating Factor), inhibition of PAF-induced accumulation of eosinophils and platelets in the airways, suppression of the priming of eosinophils by human recombinant cytokines and antagonism of bronchoconstriction due to leukotrienes. Ketotifen is marketed under many brand names worldwide. Ketotifen inhibits the release of mediators from mast cells involved in hypersensitivity reactions. Decreased chemotaxis and activation of eosinophils have also been demonstrated. Ketotifen also inhibits cAMP phosphodiesterase.

Olopatadine is an antihistamine (as well as anticholinergic and mast cell stabilizer) used to treat itching associated with allergic conjunctivitis (eye allergies). Olopatadine is a selective histamine H1 antagonist that binds to the histamine H1 receptor. This blocks the action of endogenous histamine, which subsequently leads to temporary relief of the negative symptoms brought on by histamine. Olopatadine is devoid of effects on alpha-adrenergic, dopamine and muscarinic type 1 and 2 receptors. Some known side effects include a headache (7% of occurrence), eye burning and/or stinging (5%), blurred vision, dry eyes, foreign body sensation, hyperemia, keratitis, eyelid edema, pruritus, asthenia, sore throat (pharyngitis), rhinitis, sinusitis, and taste perversion.

Olopatadine is an antihistamine (as well as anticholinergic and mast cell stabilizer) used to treat itching associated with allergic conjunctivitis (eye allergies). Olopatadine is a selective histamine H1 antagonist that binds to the histamine H1 receptor. This blocks the action of endogenous histamine, which subsequently leads to temporary relief of the negative symptoms brought on by histamine. Olopatadine is devoid of effects on alpha-adrenergic, dopamine and muscarinic type 1 and 2 receptors. Some known side effects include a headache (7% of occurrence), eye burning and/or stinging (5%), blurred vision, dry eyes, foreign body sensation, hyperemia, keratitis, eyelid edema, pruritus, asthenia, sore throat (pharyngitis), rhinitis, sinusitis, and taste perversion.

Olopatadine is an antihistamine (as well as anticholinergic and mast cell stabilizer) used to treat itching associated with allergic conjunctivitis (eye allergies). Olopatadine is a selective histamine H1 antagonist that binds to the histamine H1 receptor. This blocks the action of endogenous histamine, which subsequently leads to temporary relief of the negative symptoms brought on by histamine. Olopatadine is devoid of effects on alpha-adrenergic, dopamine and muscarinic type 1 and 2 receptors. Some known side effects include a headache (7% of occurrence), eye burning and/or stinging (5%), blurred vision, dry eyes, foreign body sensation, hyperemia, keratitis, eyelid edema, pruritus, asthenia, sore throat (pharyngitis), rhinitis, sinusitis, and taste perversion.

Emedastine is an antihistaminic agent, which was approved by FDA for the treatment of allergic conjunctivitis (Emadine brand name). The drug acts selectively on H1 receptors with lower affinity to H2 and H3 subtypes. Emedastine has a relatively unfavorable CNS effect profile. A small percentage of patients reported somnolence as an adverse effect after administration.

Emedastine is an antihistaminic agent, which was approved by FDA for the treatment of allergic conjunctivitis (Emadine brand name). The drug acts selectively on H1 receptors with lower affinity to H2 and H3 subtypes. Emedastine has a relatively unfavorable CNS effect profile. A small percentage of patients reported somnolence as an adverse effect after administration.