ECHOTHIOPHATE IODIDE FOR OPHTHALMIC SOLUTION IS A LONG-ACTING CHOLINESTERASE INHIBITOR FOR TOPICAL USE WHICH ENHANCES THE EFFECT OF ENDOGENOUSLY LIBERATED ACETYLCHOLINE IN IRIS, CILIARY MUSCLE, AND OTHER PARASYMPATHETICALLY INNERVATED STRUCTURES OF THE EYE. IT THEREBY CAUSES MIOSIS, INCREASE IN FACILITY OF OUTFLOW OF AQUEOUS HUMOR, FALL IN INTRAOCULAR PRESSURE, AND POTENTIATION OF ACCOMMODATION.