Cromolyn is a mast cell stabilizer. In vitro and in vivo animal studies have shown that cromolyn sodium inhibits the degranulation of sensitized mast cells, which occurs after exposure to specific antigens. Cromolyn sodium acts by inhibiting the release of histamine and SRS-A (slow-reacting substance of anaphylaxis) from the mast cell. Cromolyn is indicated in the management of patients with mastocytosis, prophylaxis (long-term control) of bronchial asthma, prevention of exercise-induced bronchospasm, prevention and treatment of seasonal and perennial allergic rhinitis The most frequently reported adverse reactions attributed to cromolyn sodium treatment were: throat irritation or dryness, bad taste, cough, wheeze, nausea.

Pemirolast is a mast cell stabilizer that acts as an antiallergic agent, it is approved in Japan for the treatment of bronchial asthma and of allergic rhinitis. Pemirolast strongly inhibits extracellular Ca2+ influx and the release of intracellular Ca2+, an important factor in the release of chemical mediators, by inhibiting inositol-phospholipid metabolism in mast cells. It also inhibits the release of arachidonic acid. Furthermore contribution of increasing effect on c-AMP based on inhibiting phosphodiesterase is suggested. Main pharmacological effects is an inhibition of release of chemical mediators, e.g. histamine, LTB4, LTC4, LTD4, PGD2, TXB2 and PAF from human lung tissues, abraded fragments of the nasal mucosa, and peripheral leukocytes, rat peritoneal exudate cells, and rat and guniea pig lung tissues.

Dipivefrin is a prodrug with little or no pharmacologically activity until it is hydrolyzed into epinephrine inside the human eye. The liberated epinephrine, an adrenergic agonist, appears to exert its action by stimulating α -and/or β2-adrenergic receptors, leading to a decrease in aqueous production and an enhancement of outflow facility. The dipivefrin prodrug delivery system is a more efficient way of delivering the therapeutic effects of epinephrine, with fewer side effects than are associated with conventional epinephrine therapy. Dipivefrin is used as initial therapy for the control of intraocular pressure in chronic open-angle glaucoma.

Hydroxyamphetamine is a derivative of amphetamines. Hydroxyamphetamine is intended mainly as local eye drops for diagnostic purposes. It is indirect sympathomimetic agent which cause dilation of the eye pupil before diagnostic test. Among the minor side effects from its use are: change in color vision, difficulty seeing at night, dry mouth, headache, increased sensitivity of eyes to sunlight, muscle stiffness or tightness and temporary stinging in the eyes. The main use of hydroxyamphetamines as eye drops is the diagnosis of Horner's syndrome which is characterized by nerve lesions. Hydroxyamphetamine hydrobromide is a component of FDA approved brand drug - Paremyd sterile ophthalmic solution (Hydroxyamphetamine hydrobromide, USP 1.0%, Tropicamide, USP 0.25%). Hydroxyamphetamine is an indirect-acting sympathomimetic, while tropicamide acts as a parasympatholytic.

Epinastine (brand names Alesion, Elestat, Purivist, Relestat) is a second-generation antihistamine and mast cell stabilizer. 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 α1-, α2-, 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. Elestat ophthalmic solution is indicated for the prevention of itching associated with allergic conjunctivitis.

Epinastine (brand names Alesion, Elestat, Purivist, Relestat) is a second-generation antihistamine and mast cell stabilizer. 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 α1-, α2-, 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. Elestat ophthalmic solution is indicated for the prevention of itching associated with allergic conjunctivitis.