About two percent of the population have an iodine allergy 1. A percentage of this
population will also have a reaction to iodine-containing agents, including povidone
iodine (PI) (Betadine®), which is the current standard of care for anti-septic
preparation for conjunctival procedures. Despite being known to have a toxic effect on
the cornea 2 and causing allergic reactions in some individuals, povidone Iodine (PI)
(Betadine®) is still the most commonly used antiseptic agent for surgical scrub.
Currently, there are no equivalent alternative prep agents available, although
chlorhexidine has occasionally served as an alternative to povidone iodine (PI)
(Betadine®) with variable results 2. Some studies have reported significantly less pain
in patients prepped with chlorhexidine compared to povidone iodine (PI) (Betadine®) 2,
and other studies have demonstrated that chlorhexidine has equal efficacy to povidone
iodine (PI)(Betadine®) in decreasing the colony forming units of microbes both in vitro
and in vivo 3. Although there have been no known reported allergies to chlorhexidine, it
is known to be toxic to the cornea (leading to severe keratitis) and has proven to be
less effective against methicillin-resistant Staphylococcus aureus(MRSA) 4.
The use of 0.01% hypochlorous acid (HOCl) in saline solution as an antiseptic agent has
been gaining popularity as a possible alternative to povidone iodine (PI) (Betadine®).
Hypochlorous acid (HOCl) is produced in vivo by neutrophils and causes oxidation of
microbial nucleotides and inactivation of microbial enzymes, leading to cell death.
Hypochlorous acid (HOCl) has a faster optimal kill-time for flora common to the eye 4,
and has proven to be non-cytotoxic and well tolerated for continuous use 4,5,6. In vitro
studies of 0.01% hypochlorous acid (HOCl) were found to have equal or more efficacious
antiseptic properties compared with povidone iodine (PI) (Betadine®) and other potential
antiseptic agents including chlorohexidine and isopropyl alcohol 4.
Currently, two concentrations of HOCl are available for commercial use: AvenovaTM with
Neutrox™ (0.01% HOCl) and an over the counter product (0.02% HOCl). Both concentrations
are used to treat blepharitis. Debabov et al5 presented toxicity data concluding that
0.01% hypochlorous acid (HOCl) (Avenova™ with Neutrox™) proved to be non-cytotoxic in
comparison to the 0.02% hypochlorous acid (HOCl) product which was cytotoxic thus
supporting the potential benefit of HOCl.
Stroman et al6 2017 concludes that hypochlorous acid (HOCl)in saline solution reduced
bacterial colony load significantly without altering the variation of remaining bacterial
species. Additionally, hypochlorous acid (HOCl) has been shown to reduce the population
of bacterial and fungal species common to the lids and lashes by ≥ 99.9% 7. Despite the
use of hypochlorous acid (HOCl) as a topical antiseptic on the eyelid, there have been no
reports of its use as an antiseptic agent for conjunctival procedures. Many studies have
confirmed that flora of the eyelid and eyelash only differ in their concentrations 8.
Since hypochlorous acid (HOCl) has been found to be effective in reducing colony forming
units and since the flora species of the conjunctiva, eyelid and eyelashes are
equivalent, we propose that hypochlorous acid (HOCl) may serve as an alternative to
povidone iodine (PI) (Betadine®) as a conjunctival procedure prep agent. Considering
there were no reported negative side effects of hypochlorous acid (HOCl) contact with the
eye, hypochlorous acid (HOCl) may prove to be a non-inferior alternative to povidone
iodine (PI) (Betadine®). This may result in lower irritation and toxicity compared to
povidone iodine (PI) (Betadine®)