What is the action of Hibiclens and Exidine on Gram-positive and Gram-negative bacteria; Residual activity?

• A. Excellent; Good; Excellent
• B. Excellent; Excellent; Good
• C. Good; Excellent; Excellent
• D. Excellent; Poor; Excellent

Answer: (A)

The key idea is how these antiseptics interact with different bacteria and how long they keep working after application. Hibiclens (chlorhexidine) is known for its strong, membrane‑disrupting action and for binding to skin, which gives a lasting antimicrobial effect (substantivity). Gram-positive bacteria have cell membranes that chlorhexidine can easily disrupt, and they are generally more susceptible, so the activity is described as excellent. Gram-negative bacteria have an outer membrane that can limit penetration, so the activity is good rather than excellent. Because of the skin binding and slow release, the residual antimicrobial effect of chlorhexidine is excellent. Exidine’s immediate broad-spectrum bactericidal action aligns with rapid kill of both Gram-positive and Gram-negative organisms, but its residual effect is not as prolonged as chlorhexidine’s; the overall pattern in this context emphasizes the superior residual activity of Hibiclens.