Pink Eye: Viral conjunctivitis, and epidemic keratoconjunctivitis (EKC) treatment

 As an eye surgeon who’s seen my share of red-eye epidemics sweep through waiting rooms like a summer storm, I often get asked: “Doc, is there anything beyond tears and time for this adenovirus nightmare?” The answer? Yes—and it may be hiding in your medicine cabinet. 

Today, we’re diving into Betadine (povidone-iodine, or PVP-I), the unsung hero for epidemic keratoconjunctivitis (EKC)— if you are not allergic (– – the way to tell if you’re allergic just to put betaine on your skin and make sure you do not break out in a rash. If you try the below drops and have worsening itching or redness, it could be an allergy). 

We will also talk about the smart use of antibiotic-steroid combination drops to dial down the viral drama. Backed by fresh trials and Cochrane wisdom, these aren’t gimmicks; they’re practical tools to slash recovery from weeks to days. Let’s unpack the science, so you can arm your practice (or your medicine cabinet) accordingly.

Why EKC Deserves More Than “Wait It Out”

EKC isn’t your garden-variety pink eye—it’s adenovirus (types 8, 19, 37) launching a full assault: watery discharge, photophobia, and those pesky subepithelial infiltrates (SEIs) that can blur vision for months in up to 50% of cases. No FDA-approved antiviral exists because the virus hunkers down intracellularly, mocking most topicals. Enter supportive care: lubricants, cold compresses, and strict hygiene to curb outbreaks. 

But recent RCTs scream for intervention—PVP-I zaps free virus particles in seconds, while judicious steroids tame inflammation without prolonging the party.

Betadine: The Virucidal Workhorse for EKC Epidemics. But it can burn pretty badly when it goes in, so be aware. We can put the drops in the refrigerator.

Betadine, that trusty 10% PVP-I solution from surgeries, dilutes beautifully to ocular-safe levels (0.6–5%) for EKC. Its free iodine shreds viral envelopes non-specifically—no resistance, pennies per dose. Pilot studies kicked it off: A 2012 trial irrigated eyes with 2% PVP-I, relieving discomfort in 75% within a week, with only mild stinging.  Fast-forward to the RAPID trial (2019): A single 5% wash in 272 patients cut symptom severity by 50% by day 4 versus tears alone, with 95% tolerability. 

The evidence snowballs. Kovalyuk et al. (2017) randomized 60 patients to 1% PVP-I washes; recovery halved to 4 days, SEIs dropped.  A massive 2024 Indian study (1,328 cases) used one-time 1% washes + standard care: Symptoms vanished in 3 days versus 7, slashing absenteeism in hotspots.  Even infants benefit—2.5% irrigation cleared pseudomembranes safely in a 2015 series.  Cochrane’s 2022 review (16 trials) rates it low-moderate certainty for faster clearance, but zero serious AEs beyond allergy risks. 

Pro Tip: Dilute 10% Betadine 1:10 for 1% (add to sterile saline under proparacaine). One-time wash or 4x/day drops for 7 days. Screen for iodine sensitivity, rinse post-wash, and pair with hygiene to halt spread. In my clinic, it’s outbreak kryptonite—patients thank me with clear eyes, not grudging patience.

Antibiotic-Steroid Drops: Adjunctive Allies, Not Solo Saviors

Antibiotics? Useless against viral EKC— they target bacteria, not adeno. But combo drops (e.g., neopolydexa (NPD drops 3x/day and ointment at night time 1/4” inside lower eyelid for 1-2 weeks or tobramycin-dexamethasone or moxifloxacin-dexamethasone) shine as adjuncts: The steroid curbs cytokine storms causing lid edema and infiltrates, while antibiotics prevent superinfection (up to 20% of EKC cases get bacterial overlays).

Evidence favors timed use post-viral control. A 2018 Phase 2 RCT tested PVP-I/dexamethasone suspension: Faster viral clearance and symptom relief versus tears, with no perforation risks.  The 2017 Kovalyuk study echoed: 1% PVP-I + 0.1% dexamethasone 4x/day sped recovery in 60 patients, halving pain scores.  For SEIs, a 2021 double-blind trial pitted 0.1% fluorometholone against cyclosporine: Steroids resolved infiltrates quicker (weeks vs. months), though cyclosporine cut recurrences.  

I don’t recommend oral steroids, but oral steroids can rescue severe pediatric cases: A 2014 study gave prednisolone to toddlers with lid-swollen EKC; edema melted in 1.8 days, enabling eye drop delivery. 

A 2023 meta-analysis (glucocorticoids in EKC) confirmed: Adjunctive steroids shorten acute symptoms without boosting complications, if started after antivirals (like PVP-I) and tapered over 1–2 weeks.  Caveat: Solo steroids pre-diagnosis risk worsening—always culture if unsure. In bacterial keratitis mimics, combos like TobraDex (tobramycin 0.3%/dexamethasone 0.1%) heal adjunctively, per SCUT trial insights. 

Pro Tip: Start combos 48 hours after PVP-I initiation, 4x/day, taper to 2x/week. Monitor IOP (steroid responders beware) and watch for rebound. It’s not overkill—it’s precision.

Wrapping Up: From Evidence to Empowerment

EKC epidemics don’t have to sideline lives—Betadine’s virucidal punch and antibiotic-steroid synergy offer real relief, backed by RCTs transforming “supportive” into “strategic.” In my practice, these tools cut follow-ups by half and restore vision faster. But they’re off-label warriors: Consult guidelines, tailor to patients, and prioritize prevention (handwashing > handshakes).

What’s your EKC war story? Drop a comment. 

Sandra Lora Cremers, MD, FACS 

References:

1.  Trinavarat A, Atchaneeyasakul LO. Treatment of epidemic keratoconjunctivitis with 2% povidone-iodine: a pilot study. J Ocul Pharmacol Ther. 2012;28(1):69-73. [PMID: 21916618] 

2.  Shorter ES, et al. Safety and tolerability of a one-time, in-office administration of 5% povidone-iodine… (RAPID study). Clin Ophthalmol. 2019;13:1691-1700. [PMID: 31401340] 

3.  Vats S, et al. One-time low concentration betadine eye wash… Rom J Ophthalmol. 2024;68(3):268-273. [PMID: 39464754] 

4.  Kovalyuk N, et al. Treatment of adenoviral keratoconjunctivitis with PVP-I 1.0% and dexamethasone 0.1%… Acta Ophthalmol. 2017;95(8):e686-e692. [PMID: 28342227]  

5.  Liu SH, et al. Topical pharmacologic interventions versus placebo for EKC. Cochrane Database Syst Rev. 2022;3:CD013520. [PMID: 35238405] 

6.  Pepose JS, et al. Randomized trial of PVP-I/dexamethasone… Am J Ophthalmol. 2018;194:7-15. [PMID: 29787732] 

7.  Park CY, et al. Oral steroid therapy as adjuvant for severe EKC in young children. Cornea. 2015;34(3):294-297. [PMID: 25522221] 

8.  Liu P, et al. Efficacy and safety of glucocorticoids in EKC: Meta-analysis. Ther Innov Regul Sci. 2023;57(3):476-483. [PMID: 36414914]