In the realm of antiseptic solutions, one compound has been gaining notable attention for its powerful antimicrobial properties: hypochlorous acid (HOCl). As the collective quest for effective and safe alternatives to traditional antiseptics intensifies, HOCl is welcomed as a compelling contender. With all this talk of antimicrobial efficacy, it is normal for one to wonder: how safe is hypochlorous acid?
The first in our three-part blog series navigates clinical literature to explore HOCl's safety in various applications, aiming to demonstrate why this compound is recognized for its uniqueness in how it offers the best of both worlds: efficacy and safety.
In recent years, hypochlorous acid (HOCl) has emerged as a rising star in various medical disciplines, garnering increasing attention for its efficacy as an antiseptic solution¹. Widely adopted in fields such as wound care, eye care, dermatology, and even dentistry, HOCl owes its popularity to a combination of remarkable effectiveness and a well-defined mechanism of action¹⁻⁷.
Unlike traditional antiseptics, HOCl operates by disrupting the cellular structures of pathogens, exerting its antimicrobial prowess without causing unnecessary harm to surrounding healthy cells¹. This unique mechanism not only contributes to its efficacy but also underscores its safety profile, setting it apart from traditional antiseptics¹⁻⁷. As concerns grow regarding the safety of conventional antiseptic agents¹, the ascent of HOCl signals a shift toward a safer and more effective approach to disinfection across diverse medical applications¹.
In the first of this three part safety profile series, we shed light on why hypochlorous acid stands out as a safer (while just as effective) alternative in the realm of antiseptic solutions.
Cytotoxicity: Not to Be Taken Lightly
When comparing the cytotoxic effects of antiseptics, hypochlorous acid (HOCl) emerges as a standout due to its notably low cytotoxicity¹⁻⁷.
Cytotoxicity—a critical facet in assessing the safety of antiseptic solutions—refers to the potential of a substance to cause harm to living cells, including human cells¹⁻³. In the realm of antiseptics, understanding cytotoxicity is paramount, as these solutions are designed to eliminate harmful microorganisms while safeguarding the host tissue¹⁻³. The safety profile of antiseptics hinges on their ability to effectively combat pathogens without adversely affecting human cells¹⁻⁷.
Hypochlorous-based antiseptic solution preparations have displayed remarkable antimicrobial effects while dually remaining non-cytotoxic⁷. Unlike conventional antiseptic agents that may pose a risk of harming host cells, HOCl has demonstrated a capacity to target and neutralize pathogens with a reduced impact on human cells¹. This characteristic is particularly impactful in medical applications where antiseptics are employed in wound care, surgical procedures, and other clinical settings¹.
HOCl's lower cytotoxicity not only underscores its efficacy in preserving the integrity of human cells but also positions it as a safer alternative to antiseptics with higher cytotoxic potential¹. For example, for health care practitioners treating the facial area, the sustained antimicrobial effects of chlorhexidine gluconate (CHG) create possible risks for both ocular- and ototoxicity¹.
In fact, a recent evaluative panel of physicians validated the concern of chlorhexidine’s ocular toxicity for physicians performing facial procedures requiring antiseptics and ultimately welcomed the safety profile of HOCl¹.
The meticulous evaluation of cytotoxic effects aids in distinguishing antiseptic solutions, allowing healthcare professionals to choose options that effectively disinfect while minimizing the risk of harm to the patient's tissues ¹⁻⁷.
The Safety Profile of Hypochlorous: Across the Lifespan
The development of an effective alternative antiseptic demands a meticulous consideration of safety across all age groups¹⁻⁴. Ensuring a broad spectrum of applicability requires thorough clinical evaluation to ascertain the antiseptic's safety profile, particularly in vulnerable populations such as neonates and the elderly.
Through this, hypochlorous acid (HOCl) has emerged as a notable frontrunner, undergoing rigorous clinical assessments in neonatal surgery², where, of course, the utmost caution is critical.
Impressively, HOCl has demonstrated its safety not only in neonatal settings², but has also been alternatively explored in clinical study with individuals ranging from 12 to 90 years old⁴ caring for chronic wounds. This extensive age range underscores the versatility and safety of HOCl as an antiseptic solution, offering a reassuring prospect for its utilization across diverse age demographics¹⁻⁴.
Contraindications & Interactions
Contraindications for the use of hypochlorous acid as an antiseptic are minimal but, as with any medical product, warrant consideration. Patients with a known sensitivity to hypochlorous acid should avoid use of the solution, although this condition is quite rare⁸. Despite the remarkable overall safety profile of HOCl, individuals with this documented hypersensitivity should avoid exposure to HOCl to prevent potential adverse reactions. The rarity of hypersensitivity to hypochlorous acid⁸ emphasizes its generally well-tolerated nature, making it a reliable choice for a wide range of patients in various clinical applications.
When it comes to interactions, caution is advised when combining use of HOCl solution with a very small number of antiseptic agents in particular.
If polyhexamethylene biguanide (PHMB) gauze packing is intended for use following wound cleansing with HOCl, it is recommended to rinse the wound bed with saline and pat dry to eliminate excess moisture before applying the PHMB gauze dressing. The simultaneous contact of HOCl and PHMB may slightly diminish the effectiveness of the latter, so this precaution is intended to avoid this result.
Lastly, HOCl solution should not be applied in conjunction with bio-debridement (maggot) dressings, as these may interfere with each other's therapeutic actions. Adhering to these guidelines ensures optimal efficacy of the respective antiseptic agents and promotes safe and effective wound management practices.
HOCl: A Rare Combination of Safety & Efficacy
Simply put, hypochlorous acid solutions offer medical professionals a unique antiseptic solution that is both safe and effective. This combination is exceedingly rare, which positions HOCl as a highly sought after solution for many treatment protocols.
- Hypochlorous acid is a naturally occurring molecule that has been clinically evaluated for its efficacy against bacterial, viral, and fungal microorganisms¹.
- While HOCl displays highly-efficacious anti-microbial properties, it is safe for host-tissues, illustrating it’s role as a non-cytotoxic antiseptic solution highly valuable in clinical applications where cytotoxic antiseptic solutions pose risks¹.
- Hypochlorous acid has been clinically evaluated in diverse age groups; including neonatal² and elderly populations⁴, where it has been proven as a safe antiseptic solution for a wide array of medical applications.
- An exploration of HOCl’s contraindications reveal minimal documented cases of such sensitivity⁸. The low prevalence of hypersensitivity to the agent display the solution’s generally well-tolerated nature and safety for application amongst wide populaces.
Curious to learn more about the safety of HOCl?
Look for our subsequent blog post in this three-part series which will focus on the ocular safety profile of HOCl and its related applications in fields such as ophthalmology and optometry.
We’ll answer questions such as:
- Is HOCl safe for direct contact with the ocular surface?
- Is HOCl safe for individuals with ocular conditions such as blepharitis and dry eye disease (DED)?
- Gold, M. H., Andriessen, A., Bhatia, A. C., Bitter Jr, P., Chilukuri, S., Cohen, J. L., & Robb, C. W. (2020). Topical stabilized hypochlorous acid: The future gold standard for wound care and scar management in dermatologic and plastic surgery procedures. Journal of cosmetic dermatology, 19(2), 270-277.
- Gözüküçük, A., & Çakıroğlu, B. (2022). Comparison of hypochlorous acid and Povidone Iodine as a disinfectant in neonatal circumcision. Journal of Pediatric Urology, 18(3), 341-e1.
- Anagnostopoulos, A. G., Rong, A., Miller, D., Tran, A. Q., Head, T., Lee, M. C., & Lee, W. W. (2018). 0.01% hypochlorous acid as an alternative skin antiseptic: an in vitro comparison. Dermatologic surgery, 44(12), 1489-1493.
- Jawale, M., Awdhesh, A., Mishra, K., Amarjeet, E., & Agrawal, P. J. Dr. Manikantha G.(2021). HYPOCHLOROUS ION BASED DRESSING: THROWBACK TO THE SURGEONS’ CHOICE. Global Journal for Research Analysis, DOI : 10.36106/gjra.
- Natarelli, N., Nong, Y., Maloh, J., & Sivamani, R. (2022). Hypochlorous Acid: Applications in Dermatology. Journal of Integrative Dermatology.
- Romano, G. L., Lazzara, F., Conti, F., Giunta, S., Drago, F., & Bucolo, C. (2021). Ocular safety profile of a new formulation based on hypochlorous acid in rabbit eye. Investigative Ophthalmology & Visual Science, 62(8), 726-726.
- Tsai, C. F., Chung, J. J., Ding, S. J., & Chen, C. C. (2023). In vitro cytotoxicity and antibacterial activity of hypochlorous acid antimicrobial agent. Journal of Dental Sciences.
- Zhe, G. C. S., Green, A., Fong, Y. T., Lee, H. Y., & Ho, S. F. (2016). Rare case of type I hypersensitivity reaction to sodium hypochlorite solution in a healthcare setting. Case Reports, 2016, bcr2016217228.