Antimicrobial activity of iodoquinol 1%-hydrocortisone acetate 2% gel against ciclopirox and clotrimazole.
Commercially available topical formulations consisting of iodoquinol 1%-hydrocortisone acetate 2%, ciclopirox 0.77%, and clotrimazole 1%-betamethasone dipropionate 0.5% were assessed for their antimicrobial activity against cultures of Micrococcus luteus, Propionibacterium acnes, methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, Corynebacterium aquaticum, Trichophyton mentagrophytes, Malassezia furfur, Microsporum canis, Candida albicans, Trichophyton rubrum, or Epidermophyton floccosum. At 1 and 5 minutes following inoculation into suspensions of each product, aliquots were removed, serially diluted, and plated onto appropriate agar to determine the log reduction in colony-forming units (CFUs) for each organism. Iodoquinol 1% produced the broadest and greatest antimicrobial activity as measured by a 3-log reduction of CFU, active against all microbes tested following incubation times of 1 or 5 minutes, except M luteus. By contrast, ciclopirox 0.77% and clotrimazole 1% showed activity against P aeruginosa and T rubrum, with ciclopirox also killing M luteus, P acnes, M canis, C albicans, and E floccosum at 5 minutes. Iodoquinol 1%-hydrocortisone acetate 2% also was the only product that showed effective antibacterial reduction of MRSA at 1 minute.
Burnett
Bruce P
BP
Primus Pharmaceuticals, Inc, Scottsdale, AZ 85251, USA. bburnett@primusrx.com
Mitchell
Calvin M
CM
D000890:Anti-Infective Agents / Q000494:pharmacology*; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage* / Q000494:pharmacology; D000935:Antifungal Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects*; D000077768:Ciclopirox; D003022:Clotrimazole / Q000494:pharmacology*; D005782:Gels; D006854:Hydrocortisone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D004103:Iodoquinol / Q000008:administration & dosage* / Q000494:pharmacology; D011728:Pyridones / Q000494:pharmacology*
D000890:Anti-Infective Agents; D000893:Anti-Inflammatory Agents; D000935:Antifungal Agents; D005782:Gels; D011728:Pyridones; D000077768:Ciclopirox; C021650:hydrocortisone acetate; D004103:Iodoquinol; D003022:Clotrimazole; D006854:Hydrocortisone