Contact sensitivity to Irgasan DP 300.

Area of Science:

• Dermatology
• Toxicology
• Cosmetic Science

Background:

• Irgasan, a common antimicrobial agent, is used in various personal care products.
• Allergic contact dermatitis (ACD) is a significant concern in cosmetic and dermatological applications.

Observation:

• Two patients developed ACD from deodorants containing Irgasan.
• Patch testing confirmed allergic reactions to Irgasan at 2%, 1%, and 0.5% concentrations.
• A blind usage test revealed mild itching and erythema with a soap containing 0.5% Irgasan.

Findings:

• Irgasan can act as a contact allergen, causing ACD in susceptible individuals.
• Reactions occurred at concentrations as low as 0.12% in a deodorant stick.
• Even individuals not primarily sensitized may react to Irgasan in products like soap.

Implications:

• Product formulations containing Irgasan require careful consideration due to its allergenic potential.
• Awareness of Irgasan's allergenicity is crucial for dermatologists and consumers.
• Further research into safer alternatives or reduced Irgasan concentrations may be warranted.