Antimicrobial Stewardship: Proper Use And Managed Risks

Antimicrobial Stewardship (AS) is an inter-professional effort involving optimal and prudent antimicrobial use for patients across the continuum of care. AS is an essential strategy for acute care, long-term care and in outpatient settings.2 In a world where antibiotics and antimicrobials show decreasing effectiveness, chlorhexidine is an ideal antimicrobial due to its broad spectrum of activity, long-lasting duration and lack of demonstrated antimicrobial resistance in a clinical setting. As with any medical antimicrobial, it is important to understand its proper uses and avoid potential risks.

Proper Use

As with any antimicrobial, care should be taken to use chlorhexidine properly. Chlorhexidine products should only be used as directed as indicated in their labeling (instructions for use or package insert). Be sure to consult the products' instructions or package insert prior to use. Chlorhexidine products are not recommended as skin preparation for lumbar puncture, epidural catheter placement or neurosurgical procedures.13

Minor Reactions

In oral use, chlorhexidine may have rare side effects, such as desquamative gingivitis, discoloration of teeth and tongue or dysgeusia (distorted taste).6,7 Though rare, these side effects do occur and are reversible with discontinuation of use.6,7,10

Chlorhexidine has also been documented to cause contact dermatitis in some people. Typically this occurs after prolonged or repeated applications. Contact dermatitis may occur in both patients and healthcare workers. It may also cause photosensitivity (skin sensitivity to sunlight), contact urticaria (rash) or occupational asthma. Chlorhexidine may also cause fixed-drug eruptions or drug-induced blisters. Topical reactions have been reported to occur in about 2% of the population.7 Irritation may be caused by the concentration of the chlorhexidine, which varies from product to product.1

Severe Reactions

In 1998, the FDA issued a Public Health Notice advising healthcare professionals of the potential for serious hypersensitivity reactions to medical devices containing chlorhexidine (intravenous catheters, topical antimicrobial skin dressings and implanted antimicrobial surgical mesh).18 In rare cases, an anaphylactic reaction can be caused by chlorhexidine.6 The suspected cause of the reaction are antibodies known as Immunoglobulin E (IgE) antibodies.7 If a patient has experienced contact dermatitis or a mild "allergic" reaction, they are at greater risk for a serious reaction.7 A severe reaction is more likely when mucous membranes, wounds or open skin are exposed to chlorhexidine.7 Hypersensitivity to chlorhexidine is rare, but with its increasing use in the healthcare setting, clinicians should be aware of the risk of possible reaction. Direct contact with the eye, inner ear or neural tissue should be avoided.23 Contact with conjunctiva may cause permanent damage, and accidental contact with the tympanum may cause ototoxicity.7

Mitigating Risk

If a patient experiences sensitivity to a product containing chlorhexidine, discontinue its use immediately. If a patient exhibits an unexplained hypersensitive reaction, assess for the use of a product containing chlorhexidine as a possible cause. If you suspect a patient has/had a hypersensitivity reaction to a product, drug or medical device that contains a chlorhexidine compound, monitor the reaction carefully, provide immediate respiratory and/or cardiovascular support as needed and discontinue the use of the drug or medical device immediately. Appropriate treatment for the sensitivity reaction should be followed. Finally, follow established policy/procedures for adverse event reporting and reporting to the manufacturer or FDA as required by federal law.

A blood test may be used to confirm chlorhexidine sensitivity. Measurement of chlorhexidine-related IgE is done by an ELISA test available from Phadia AB®, a subsidiary of Thermo Fisher Scientific®, called ImmunoCAP250, and by HR-test (histamine release) available from Reflab ApS®. Completed studies may confirm chlorhexidine allergy that is IgE-mediated and a measurement of specific IgE and histamine release are good adjuncts to skin testing in patients with clinical history suggesting chlorhexidine sensitivity. Clinical implications: IgE and histamine release testing can be used to support the diagnosis of allergy to chlorhexidine.19

ImmunoCAP 250, Phadia AB and Thermo Fisher Scientific are trademarks or registered trademarks of Thermo Fisher Scientific.

Reflab ApS is a trademark or registered trademark of Reflab ApS.