What is the use of Iodoquinol (diiodohydroxyquinoline) ointment?

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Last updated: March 14, 2025 • View editorial policy

From the Guidelines

Iodoquinol (diiodohydroxyquinoline) ointment is used to treat fungal infections, including those of the external ear canal, and can be applied topically as part of local measures in immunocompetent patients or those with lesser severity infections. When considering treatment options for fungal infections such as those caused by Aspergillus species, it's crucial to differentiate between invasive and non-invasive infections, as well as the patient's immune status 1. For non-invasive or less severe infections in immunocompetent patients, local measures including the use of topical antifungal agents can be effective. Some of the topical therapeutic options that have been used include nystatin, amphotericin B, and iodochlorhydroxyquin, among others 1. Given the context of treating fungal infections, the application of iodoquinol ointment as part of these local measures can be beneficial, especially when systemic antifungal therapy is not necessary. It's essential to follow the recommended application guidelines and monitor for any side effects, ensuring the best outcome for the patient. In the management of fungal infections, particularly those affecting the external ear canal, a thorough assessment of the infection's severity and the patient's immune status is critical to determine the most appropriate treatment approach, which may include the use of iodoquinol ointment as part of local therapeutic measures.

From the FDA Drug Label

Each gram of Hydrocortisone 1% – Iodoquinol 1% Cream contains 10 mg of hydrocortisone and 10 mg of iodoquinol in a greaseless base of cetyl alcohol, glyceryl monostearate SE, isopropyl myristate, lanolin alcohol, mineral oil, polyoxyl 40 stearate, polysorbate 20, polysorbate 60, propylene glycol, purified water, sorbic acid, and sorbitan monostearate. ... iodoquinol, 5,7-diiodo-8-quinolinol (C9H5I2NO) is represented by the following structure: Hydrocortisone is an anti-inflammatory and antipruritic agent, while iodoquinol is an antifungal and antibacterial agent.

The use of Iodoquinol (diiodohydroxyquinoline) ointment is as an antifungal and antibacterial agent 2.

From the Research

Use of Iodoquinol (Diiodohydroxyquinoline) Ointment

  • Iodoquinol is used as an antimicrobial agent in topical formulations, exhibiting broad-spectrum activity against various microorganisms 3.
  • The antimicrobial activity of iodoquinol 1%-hydrocortisone acetate 2% gel has been assessed against cultures of Micrococcus luteus, Propionibacterium acnes, methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa, and other microbes, showing a 3-log reduction in colony-forming units (CFUs) for most organisms tested 3.
  • Iodoquinol 1% has been found to produce the broadest and greatest antimicrobial activity among the tested products, active against all microbes except M. luteus 3.
  • However, there is limited information available on the specific use of iodoquinol ointment, and its effectiveness against various skin infections and conditions 4, 5, 6, 7.

Antimicrobial Activity

  • Iodoquinol has been shown to exhibit effective antibacterial reduction of MRSA at 1 minute, making it a potential agent for the treatment of skin infections caused by this microorganism 3.
  • The antimicrobial activity of iodoquinol is comparable to other topical agents, such as ciclopirox and clotrimazole, although its spectrum of activity may differ 3.
  • Further studies are needed to fully understand the clinical efficacy and potential uses of iodoquinol ointment in the treatment of skin infections and other conditions 4, 5, 6, 7.

Comparison with Other Topical Agents

  • Iodoquinol has been compared to other topical antimicrobial agents, such as gentamicin, chloramphenicol, and nystatin, in terms of its antimicrobial activity and potency 4.
  • The minimum inhibitory concentration (MIC) values of iodoquinol have been found to vary depending on the microorganism and the specific formulation used 4.
  • Further research is needed to determine the optimal use of iodoquinol ointment in comparison to other topical agents for the treatment of skin infections and other conditions 5, 6, 7.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

The role of fluoroquinolones in skin and skin structure infections.

American journal of clinical dermatology, 2002

Research

Fusidic acid in skin infections and infected atopic eczema.

Giornale italiano di dermatologia e venereologia : organo ufficiale, Societa italiana di dermatologia e sifilografia, 2014

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.