Unlike Systane and Genteal ointments, which are petrolatum/mineral oil emollients designed simply to protect the corneas from contact-related stress (thereby soothing irritated dry eyes for a while), Muro is a much older petrolatum/mineral oil/lanolin/5% saline product designed, via its hypertonicity, to draw significant amounts of fluid out of waterlogged corneas. Corneas can get waterlogged as a reaction to ocular surgeries and in corneal diseases like Fuchs dystrophy, in which the basement membrane of the cornea doesn´t function optimally, allowing the corneal epithelium to loosen. Severe dry eye can also indirectly damage the corneal epithelium simply by virtue of inadequacy of the ocular tear film, leading to recurrent corneal erosion (especially during sleep). The salt concentration in Muro works wonderfully to tighten up loose/fragile corneal epithelium by drawing excess fluid out of the cornea regardless of the cause of this epithelial fragility. So Muro has traditionally been prescribed or recommended to dry eye patients who have recurrent corneal erosion, and for whom, therefore, blank ointments, like Systane/Genteel/Refresh P.M./Soothe, etc. will not be enough to prevent the recurring erosion. My recurrent corneal erosion is extremely mild, but my wonderful eye doctor opted to put me on Muro ointment long term because over time, stopping even a minor erosion cycle can greatly reduce corneal pain. Today, many different OTC eyedrops for dry eye are able to normalize some patients´ tear films (albeit temporarily), and so the prevailing treatment even for severe dry eye, other than the Rx products like Restasis, Xiidra, and varenicline nasal spray, are OTC drops like FreshKote (high oncotic pressure drops) and Optase MGD (with sacha inchi oil); and FreshKote, in particular, can normalize the tear filmś ability to wet the cornea so substantially that it is sometimes used in place of or together with Muro drops or ointment for dry eye patients with corneal erosions. In any case, Muro ointment has the potential to help me with my impaired nasal airflow by creating a pool of fluid from my slightly waterlogged corneas that then drains into my nasal passages after traveling through my nasolacrimal ducts. This fluid has the potential to moisten or humidify my severely dry post-COVID nasal passages, and if any of the saline and petrolatum base from Muro is also making its way into my nostrils, possibly these ingredients may provide their own, separate moisturizing effects. I cannot tolerate any nasal ointments or sprays (especially after months of wrecking my nasal passages with steroidal and antihistamine sprays loaded with preservative BAK), so the use of ophthalmic Muro as a less direct way of getting moisture into the nose seemed worth a try.
I appreciate your explanation. I wonder why my ophthalmologist has never mentioned Muro. I have dry eye and Salzman’s Nodules.
I have been seeing a cornea specialist at Duke for several years and before that with cornea specialist at UNC….I wonder why they never mentioned it. Just said use products without preservatives. I use ointment at night and lubricant drops during the day as needed.
I can’t use the prescription drops for dry eye. Just irritate my eyes.
I had a prescription for plasma drops, but haven’t gotten it filled, since my insurance doesn’t cover them.