How do they work?

Products labeled as insect repellents are not designed to kill insects but keep them away to prevent bites and the spread of disease. Permethrin is the exception and is an insecticide that kills pests on contact when applied to clothing and gear.

Repellent Options

Use only Environmental Protection Agency (EPA)-registered repellents. Look for the EPA registration number listed on the product. When used as directed, EPA-registered insect repellents are proven safe and effective.

  • Treat clothing and gear with permethrin, purchase permethrin-treated clothing, or use Insect Shield’s repellent clothing treatment service.
  • Spray exposed skin with EPA-registered repellents containing one of the following active ingredients: DEET, picaridin, IR3535, oil of lemon eucalyptus (OLE), or p-menthane-3,8-diol (PMD). Visit www.epa.gov/insect-repellents/find-repellent-right-you for product-specific information for repellent products. Repellents can also be used on clothing and gear; however, pay attention to compatible materials.

Repellent

DEET*

Picaridin

IR3535

Oil of lemon eucalyptus/P-methane-3,8-diol

Permethrin

What can it be used on?

Made for use on skin; however, it may also be applied to clothing and gear, but pay attention to compatible materials.

Apply only to clothes, shoes, and other fabrics.

Never apply directly to skin!

What materials is it safe to use on?

Safe for use on cotton, wool, and nylon. May damage spandex, rayon, acetate, and pigmented leather and dissolve plastic and vinyl.

No damage to plastics or clothing but can discolor leather and vinyl.

May damage plastic and clothing.

No Information.

No damage to plastics or clothing.

Is it effective? How long does it last?

Highly effective.

Lasts 2 to 8 hours, depending on concentration.

Highly effective.

Lasts 3 to 10 hours, depending on concentration.

Moderately effective. Lasts 4 to 6 hours.

Highly effective. Lasts up to 2 hours.

Highly effective repellent & contact insecticide. 0.5% sprays applied to clothing can last for 5 to 7 washes.

What can it repel? **

Mosquitoes, ticks, fleas, black flies, biting midges

Mosquitoes, ticks, fleas, black flies, biting midges

Mosquitoes, ticks, black flies

Mosquitoes, ticks, fleas, black flies, biting midges, gnats

Mosquitoes, ticks, fleas, black flies, human lice, chiggers

Other names for ingredient

N, N-diethyl-meta-toluamide

Icaridin, Piperidine, Propidine, INCI, KBR 3023

Ethyl butyl acetyl aminopropionate

OLE/PMD

Table adapted from Cornell’s Insect Repellent Essentials3.

*Products containing concentrations higher than 50% DEET do not increase the length of protection. For most situations, 10% to 25% DEET is adequate.

**Products with lower concentrations of these ingredients may not be as effective at repelling ticks. Always look on the product label to see what pests are effectively targeted by the active ingredient.

 

Treating Clothes and Gear with Permethrin

☐ Do NOT use permethrin directly on skin. It can be harmful if absorbed through the skin. Treat only clothing and gear with permethrin.

☐ Follow instructions on the product label to apply permethrin to clothing and gear.

☐ Wear protective gloves and apply permethrin in a ventilated area (outdoors).

☐ Hang clothing and gear outside to dry completely before use.

☐ Wash permethrin-treated clothing separately from non-treated clothes. Permethrin-treated clothing provides protection after multiple washings.

☐ Re-treat clothing as needed.

☐ Warning: Wet permethrin is toxic to cats. Keep permethrin, products used to apply permethrin, and permethrin-treated clothing and equipment away from your cat. Permethrin is also harmful to fish, aquatic invertebrates, bees, and other beneficial insects, so do not spray permethrin near flowers or water sources.

How to Apply Repellents Approved for use on Skin

The instructions below are for repellents meant for use on skin that contain one of the following active ingredients: DEET, picaridin, IR3535, oil of lemon eucalyptus (OLE), or p-menthane-3,8-diol (PMD).

☐ Follow instructions on the product label.

☐ Apply repellents only to exposed skin or clothing, never underneath clothing.

  • If sunscreen is needed, apply sunscreen first, then wait several minutes before applying repellent. Avoid combination products by using separate sunscreen and repellents for protection.
  • Warning: If applying repellents to clothing, apply to the outward-facing surface and be aware of what materials are compatible with the repellent.

☐ Never spray repellents over cuts, wounds, sunburns, rashes, or irritated skin.

☐ Do not spray directly on the face – spray on hands first and then apply to the face.

☐ Do not apply repellents to eyes or mouth and use sparingly around ears.

☐ Do not spray in enclosed areas or near food, and avoid inhaling or ingesting repellents during application.

☐ Wash hands after application to avoid accidental exposure to eyes or mouth.

☐ Avoid heavy application – use just enough repellent to cover exposed skin or clothing.

☐ Maximize effectiveness by applying and reapplying a repellent according to the label instructions.

  • When sunscreen is used, it should be reapplied every few hours; however, insect repellents last longer and should only be reapplied per the label instructions.

☐ After returning indoors, wash repellent-treated skin with soap and water.

Resources

  1. CDC – Prevent Tick and Mosquito Bites: https://www.cdc.gov/ncezid/dvbd/about/prevent-bites.html
  2. CDC – Mosquitoes: How to Use Permethrin: https://www.cdc.gov/mosquitoes/mosquito-bites/how-to-use-permethrin.html
  3. Cornell’s Insect Repellent Essentials: A Brief Guide: https://hdl.handle.net/1813/66722
  4. Diaz, J.H., 2016. Chemical and plant-based insect repellents: efficacy, safety, and toxicity. Wilderness Environ. Med. 27, 153-163. https://www.sciencedirect.com/science/article/pii/S1080603215004342
  5. Dymond, NL, Swift, IM. Permethrin toxicity in cats: A retrospective survey of 20 cases. Aust Vet J 2008; 86: 219-23. https://onlinelibrary.wiley.com/doi/full/10.1111/j.1751-0813.2008.00298.x
  6. EWG – EWG’s 2018 Guide to Bug Repellents: https://www.ewg.org/consumer-guides/ewgs-2018-guide-bug-repellents
  7. EPA – Find the Repellent that is Right for You: https://www.epa.gov/insect-repellents/find-repellent-right-you
  8. EPA – Permethrin Facts: https://www3.epa.gov/pesticides/chem_search/reg_actions/reregistration/fs_PC-109701_1-Jun-06.pdf
  9. EPA – Repellents: https://www.epa.gov/insect-repellents
  10. IDPH – DEET Insect Repellents: https://www.dph.illinois.gov/topics-services/environmental-health-protection/structural-pest-control/deet-insect-repellents
  11. Katz T, Miller J, Herbert A. Insect repellents: Historical perspectives and new developments. JAAD 2008;58:865-871. https://www-sciencedirect-com.proxy2.library.illinois.edu/science/article/pii/S0190962207014673
  12. NPIC – Permethrin Technical Fact Sheet: http://npic.orst.edu/factsheets/archive/Permtech.html
  13. TickEncounter – The University of Rhode Island: https://web.uri.edu/tickencounter/ticksmart/
  14. The Medical Letter – Insect Repellents: https://secure.medicalletter.org/w1579b
  15. The University of Maine – Pest Management Fact Sheet: https://extension.umaine.edu/ipm/ipddl/publications/5108e/
Last Updated: 10/27/2021