Phospholine Iodide
(Echothiophate Iodide For Ophthalmic Solution)Phospholine Iodide Prescribing Information
Echothiophate iodide for ophthalmic solution is indicated for the reduction of elevated IOP.
- Active uveal inflammation.
- Most cases of angle-closure glaucoma without iridectomy, due to the possibility of increasing angle block.
- Hypersensitivity to the active or inactive ingredients.
- Although the relationship, if any, of retinal detachment to the administration of echothiophate iodide for ophthalmic solution has not been established, retinal detachment has been reported in a few cases during the use of echothiophate iodide for ophthalmic solution in adult patients without a previous history of this disorder.
- Stinging, burning, lacrimation, lid muscle twitching, conjunctival and ciliary redness, browache, induced myopia with visual blurring may occur.
- Activation of latent iritis or uveitis may occur.
- Iris cysts may form, and if treatment is continued, may enlarge and obscure vision. This occurrence is more frequent in children. The cysts usually shrink upon discontinuance of the medication or by reducing the frequency of instillation. Rarely, they may rupture or break free into the aqueous. Regular examinations are advisable when the drug is being prescribed for the treatment of accommodative esotropia.
- Prolonged use may cause conjunctival thickening, obstruction of nasolacrimal canals.
- Lens opacities have been reported with echothiophate iodide.
- Paradoxical increase in IOP may follow anticholinesterase instillation. This may be alleviated by prescribing a sympathomimetic mydriatic such as phenylephrine.
- Cardiac irregularities.
Echothiophate iodide for ophthalmic solution potentiates other cholinesterase inhibitors such as succinylcholine or organophosphate and carbamate insecticides. Patients undergoing systemic anticholinesterase treatment should be warned of the possible additive effects of echothiophate iodide for ophthalmic solution.
Chemical name: (2-mercaptoethyl) trimethylammonium iodide O,O-diethyl phosphorothioate
Structural formula
Echothiophate iodide for ophthalmic solution occurs as a white, crystalline, water-soluble, hygroscopic solid having a slight mercaptan-like odor. When freeze-dried in the presence of potassium acetate, the mixture appears as a white amorphous deposit on the walls of the bottle.
Each package contains materials for dispensing 5 mL of eyedrops: (1) bottle containing sterile echothiophate iodide for ophthalmic solution 6.25 mg (0.125%) with 40 mg potassium acetate. Sodium hydroxide or acetic acid may have been incorporated to adjust pH during manufacturing; (2) a 5 mL bottle of sterile diluent containing chlorobutanol (chloral derivative), 0.55%; mannitol, 1.2%; boric acid, 0.06%; and sodium phosphate, 0.026%; (3) sterilized dropper.
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 (IOP), and potentiation of accommodation.
Echothiophate iodide for ophthalmic solution will depress both plasma and erythrocyte cholinesterase levels in most patients after a few weeks of eyedrop therapy.