If a patient has a known iodine allergy, what is the appropriate antiseptic choice during preoperative skin prep?

• A. Use povidone-iodine
• B. Use chlorhexidine gluconate in alcohol (CHG in alcohol)
• C. Use plain water
• D. Use a topical antibiotic ointment

Answer: (B)

The best choice is chlorhexidine gluconate in alcohol. If the patient has an iodine allergy, you avoid povidone-iodine because it contains iodine and could trigger a reaction. Chlorhexidine is not iodine-based and provides strong, broad-spectrum antisepsis with rapid kill and persistent activity on the skin when used with an alcohol base. The alcohol enhances immediate microbial reduction, and CHG adheres to the skin, offering ongoing protection during surgery. Plain water does not provide adequate antisepsis, and a topical antibiotic ointment is not suitable as the primary skin prep for surgery and does not achieve the same broad, rapid reduction in skin flora.