Olopan DS® is a sterile ophthalmic solution containing olopatadine, a relatively selective H1-receptor antagonist and inhibitor of histamine release from the mast cell for topical administration to the eyes Olopan DS® (Olopatadine) is indicated for the treatment of the signs and symptoms of allergic conjunctivitis. The recommended dose is one drop in each affected eye once in a day. Headaches have been reported at an incidence of 7%. The following adverse experiences have been reported in less than 5% of patients: Asthenia, blurred vision, burning or stinging, cold syndrome, dry eye, foreign body sensation, hyperemia, hypersensitivity, keratitis, lid edema, nausea, pharyngitis, pruritis, rhinitis, sinusitis, and taste perversion. Every plastic dropper bottle contains 5 ml sterile eye drops. Each ml contains Olopatadine Hydrochloride INN 2 mg.