What is a common contraindication for CHG-based skin prep?

• A. Latex allergy
• B. History of diabetes
• C. Age over 90
• D. Known allergy to chlorhexidine or contact dermatitis, and CHG near mucous membranes or open wounds

Answer: (D)

Chlorhexidine-based skin prep is avoided when there is a known allergy to chlorhexidine or a history of chlorhexidine-induced contact dermatitis, and when CHG would contact mucous membranes or open wounds. Allergy or dermatitis means the skin could react severely, while contact with mucous membranes or broken skin increases absorption and the risk of irritation or systemic effects. Latex allergy, diabetes, or advanced age aren’t, on their own, contraindications to CHG, though they may influence your choice of prep in some cases.