What is a key advantage of chlorhexidine gluconate in alcohol for skin prep?

• A. It has no residual activity
• B. Rapid, broad-spectrum antimicrobial activity with potential residual effect on intact skin
• C. It only works on mucous membranes
• D. It is nonflammable

Answer: (B)

The advantage comes from a combination that yields both a rapid kill and lasting protection. Alcohol provides quick, broad-spectrum antimicrobial action by disrupting cell membranes and proteins, so contaminants on the skin are killed rapidly. Chlorhexidine gluconate then binds to skin surfaces, especially keratin, and is released slowly over time, giving a persistent antimicrobial effect—substantivity—even after the prep has dried. This means patients start surgery with a markedly reduced microbial load and maintain lower counts for hours into the procedure, which helps lower the risk of surgical site infections. It isn’t correct that there is no residual activity, and it isn’t limited to mucous membranes; plus, because the formulation includes alcohol, it is flammable, so it is not nonflammable.