Treatment for Formalin Exposure to the Eye
Begin immediate copious irrigation with tap water for at least 15 minutes at the scene of exposure—this is the single most critical intervention to prevent permanent vision loss from formalin chemical burns. 1, 2
Immediate Decontamination (First Priority)
Start irrigation immediately with whatever water is available—do not delay to search for "better" solutions or to transport the patient. 1, 2 Every second counts in preventing irreversible tissue damage from formalin, which acts as a corrosive chemical agent.
Use large volumes of clean tap water continuously for a minimum of 15 minutes, extending up to 30 minutes to 2 hours for massive exposures. 1, 3 Tap water is readily available, safe, and effective as the preferred irrigation fluid.
If immediately available, normal saline, Ringer's lactate solution, or commercial eye wash solutions are reasonable alternatives, though you should never delay irrigation to obtain these. 1, 2
Direct the irrigation flow away from the uninjured eye to avoid converting a unilateral injury into a bilateral one. 1, 4 This is a critical technical point that prevents cross-contamination.
Assist patients in keeping their eyelids open during irrigation, as they may reflexively close them due to pain. 1, 4
Continue irrigation until a healthcare professional can evaluate the injury and confirm that the pH of the eye has returned to normal (pH 7.0-7.4). 1, 2
Urgent Ophthalmologic Assessment
Arrange immediate ophthalmology consultation for all formalin exposures beyond trivial splashes. 3 Formalin can cause severe ophthalmic damage including eyeball deformation, cataract formation, and tissue necrosis. 5
Use topical fluorescein eye drops to assess the extent of epithelial loss on both the cornea and conjunctiva. 1
Apply topical local anesthetic (proparacaine or tetracaine) prior to examination if needed for patient comfort. 1
Classify the severity of chemical injury using the Roper-Hall classification system to guide prognosis and treatment intensity. 6
Post-Exposure Medical Management
Intensive Lubrication
- Apply nonpreserved hyaluronate or carmellose eye drops every 2 hours throughout the acute phase (typically 7-14 days or until complete epithelial healing). 1 This maintains corneal epithelial integrity and promotes healing.
Infection Prophylaxis
- Initiate broad-spectrum topical antibiotic prophylaxis (moxifloxacin or levofloxacin four times daily) if any corneal fluorescein staining or epithelial defect is present. 1 This prevents secondary bacterial infection of the damaged corneal surface.
Anti-Inflammatory Treatment
Consider topical corticosteroid drops (dexamethasone 0.1% twice daily) to reduce ocular surface inflammation, but only under direct ophthalmologic supervision. 1 Corticosteroids can mask signs of corneal infection and should be used with caution.
Administer topical cycloplegics to reduce pain from ciliary spasm and prevent posterior synechiae formation. 6
Daily Debridement
- Perform daily mechanical removal of pseudomembranes and debris during the acute phase using saline irrigation, a squint hook, and forceps under direct visualization. 1 This prevents accumulation of inflammatory material that impairs healing.
Ongoing Monitoring
- Provide daily ophthalmologic review during the acute illness to assess healing progress, adjust treatment, and detect complications early. 1 This is mandatory for moderate to severe exposures.
Critical Pitfalls to Avoid
Never delay irrigation to transport the patient or obtain specialized equipment—immediate decontamination at the scene is paramount. 1, 2
Do not contaminate the unaffected eye, other individuals, or surrounding areas during irrigation. 4, 2
Do not underestimate the severity of formalin injuries—they can cause devastating ocular and systemic morbidity including pulmonary complications. 6
Long-Term Complications to Monitor
Corneal opacities (nebulo-macular scarring) occur in approximately 12% of chemical burn cases. 6
Secondary glaucoma and dry eye syndrome may develop as late sequelae. 6
Esophageal strictures and gastric outlet obstruction can occur if formalin is ingested, with a latent period for esophageal carcinoma extending up to 60 years. 3