Alternative Insect Repellents for DEET-Related Rash
For individuals who develop a rash from DEET, picaridin (also called icaridin) at concentrations >15% is the preferred alternative insect repellent, as it provides comparable efficacy to DEET without cross-reactivity in DEET-sensitive individuals. 1
Primary DEET Alternative: Picaridin
Picaridin at concentrations >15% repels as well as DEET when applied to skin and is considered an effective DEET alternative. 1 The CDC specifically identifies picaridin (1-piperidinecaboxylic acid, 2-[2-hydroxyethyl], 1-methlypropyl ester) as providing similar protection time to DEET 15% at 20% concentration. 2
Clinical evidence demonstrates that patients with contact urticaria to DEET can safely tolerate picaridin-based repellents without cross-reactivity. 3 In documented cases, individuals showing immediate urticarial responses to 7% DEET had negative patch tests to 5% picaridin, confirming it as an acceptable alternative. 3
Picaridin is as potent as DEET but less toxic, with the advantage of having longer-lasting action among available synthetic repellents. 4
Secondary Alternative: IR3535
IR3535 (3-[N-Butyl-N-acetyl]-aminopropionic acid, ethyl ester) at concentrations >15% provides DEET-comparable protection and has the lowest toxicity profile among synthetic repellents. 1
IR3535 is specifically recommended for children over 6 months of age and pregnant women due to its lower toxicity levels compared to DEET. 4
This compound may be prescribed when both efficacy and minimal toxicity are priorities, though it shares similar repellent mechanisms with picaridin. 4
Clothing-Based Protection: Permethrin
Permethrin should be applied to outer clothing (shirts, pants) and never directly to skin, as it is inactivated by skin lipids. 1
Permethrin-impregnated clothing reduces tick bites by >80% among outdoor workers and kills ticks on contact. 1
Pre-treated clothing remains effective for multiple launderings, and spray-on preparations should be applied evenly in well-ventilated areas with complete drying before wearing. 1
Important Application Guidelines
When using alternative repellents:
Apply repellents only to exposed skin or clothing, avoiding application to broken or irritated skin. 1
Products should be used according to EPA label instructions, with particular attention to frequency of reapplication. 1
After returning indoors, wash treated skin with soap and water. 1
Avoid applying to hands, face (unless necessary), or any abraded skin areas. 1
Critical Caveats
Repellents labeled for mosquitoes, fleas, or other arthropods may not be effective tick repellents, and repellency varies by tick species. 1
No repellent provides 100% protection against insect-borne diseases. 2
Plant-derived essential oil repellents have low toxicity but reduced action time due to rapid evaporation, requiring more frequent reapplication. 4
Combining repellents with protective clothing (long-sleeved shirts, pants tucked into socks) and environmental awareness provides optimal protection. 1, 2