Using Insect Repellent Safely

What is an insect repellent?
An insect repellent is a chemical which repels mosquitoes and other biting, crawling and annoying insects. Insect repellents do not kill insects; rather they make the person wearing repellent unattractive to the insects. Repellents are effective only at short distances from the treated surface, so you may still see mosquitoes flying nearby.

Why should I use insect repellent?
Using insect repellent is the most effective way to reduce your exposure to mosquito and tick bites. Protecting yourself and your family from these bites will also offer protection from exposure to the pathogens that cause West Nile virus and Lyme disease while allowing you to continue to play and work outdoors.

When should I use insect repellent?
Insect repellents are recommended for use in any outdoor activities where there is a risk of being bitten by mosquitoes or ticks. Repellent should be re-applied if you are being bitten. Re-application depends on the repellent, the strength of the repellent, and the amount of time you are outside. If you sweat or get wet you may need to re-apply repellent more frequently. Always follow the directions on the product you are using.

Which mosquito repellent works the best?
The Centers for Disease Control and Prevention (CDC) recommends the use of the following on skin:

  • DEET ( chemical name N,N-diethyl-m-toluamide)
  • Picaridin (chemical name: KBR 3023 or Bayrepel)
  • IR 3535 (chemical name: 3-[N-butyl-N-acetyl]-aminopropionic acid)
  • Oil of Lemon Eucalyptus (chemical name: p-menthance 3,8-diol or PMD)

Picaridin, IR 3535 and Oil of Lemon Eucalyptus are fairly new products in the United States, but DEET has been used in the US since the 1950s.

The CDC recommends using products that have been scientifically proven to repel mosquitoes and ticks and that contain active ingredients which have been registered with the US Environmental Protection Agency (EPA) for use as insect repellents on skin or clothing. Additional research suggests that repellents containing DEET or picaridin typically provide longer-lasting protection than the other products, and oil of lemon eucalyptus provides longer lasting protection than other plant-based repellents.

Choose a repellent that provides protection for the amount of time that you will be outdoors. Products containing a higher concentration (higher percentage) of active ingredient provide longer-lasting protection-check the label for percentage and re-application rates. Repellents can be purchased at your local drug store and supermarket, although 'outdoor' stores will usually have a wider variety of these products for sale.

The best repellent is the one you will use. Use a repellent to protect yourself from mosquito- and tick-borne diseases.

Picture of a bottle of mosquitoe repellent. Picture of a bottle of mosquitoe repellent.

Is DEET safe?
Products containing DEET are very safe when used according to the directions. Since DEET is so widely used, a great deal of testing has been done. DEET has been used to repel mosquitoes and ticks for over 40 years and in this time there have been very few confirmed incidents of toxic reactions to DEET.


The American Academy of Pediatrics (AAP) Committee on Environmental Health has recently updated their recommendation for use of DEET products on children, stating that insect repellents containing up to 30% DEET are safe for use on anyone older than 2 months of age.

For more information about using insect repellents containing DEET read our DEET Sheet (Large PDF file 140K).

Are the new products Picaridin, IR 3535 and Oil of Lemon Eucalyptus any good?

Yes. According to research reviewed by CDC, Picaridin (often labeled as KBR 3023 or Bayrepel) typically provides long lasting protection and is similar to DEET in its efficacy. IR 3535 (3-[N-butyl-N-acetyl]-aminopropionic acid) does repel mosquitoes, but the length of effectiveness appears to be shorter than that of DEET, so reapplication is necessary more often. Oil of lemon eucalyptus (p-menthane-3,8-diol [PMD]) has been found to provide longer lasting protection than the other plant-based repellents.

For more information on these products, go to the Centers for Disease Control's repellent update page.

Note: Recommendations for IR-3535, picaridin or oil of lemon eucalyptus use against ticks have not been made by the CDC. Only DEET is currently recommended in preventing tick bites.

What are some general considerations to remember when using insect repellents?

  • Always follow the label instructions when using repellents.
  • Apply enough repellent to cover exposed skin or clothing.
  • Do not apply repellent to skin that is under clothing. Heavy application is not necessary to achieve protection.
  • Do not apply repellent to cuts, wounds, or irritated skin.
  • After returning indoors, wash treated skin with soap and water. (This may vary depending on the product. Check the label.) Wash treated clothing before wearing again.
  • Do not spray aerosol or pump products in enclosed areas.
  • Do not spray aerosol or pump products directly to your face. Spray your hands and then rub them carefully over the face-avoid or use sparingly around the eyes, mouth, and ears.
  • Use separate repellent and sunscreen products as they need to be re-applied at different times.
If you or your child have an adverse reaction after using a repellent, discontinue using the repellent, wash the affected areas, and contact your physician or a local poison control center.

Can insect repellents be used on children?
Repellent products must state any age restriction. If there is none, EPA has not required a restriction on the use of the product. Parents should choose a repellent type and concentration by taking into account the amount of time that a child will be outdoors, their exposure to mosquitoes, and the risk of mosquito-transmitted disease in the area. Children should not handle repellents. Apply repellent to your own hands first and then put it on the child. You may not want to apply it to the child's hands as children tend to put their hands in their mouths.

  • DEET: The American Academy of Pediatrics (AAP) recommends that repellents with up to 30% DEET can be used on infants and children greater than 2 months of age.
    Since it is the most widely available repellent, many people ask about the use of products containing DEET on children. No serious illness has been linked to the use of DEET in children when used according to manufacturer's recommendations.
  • Oil of Lemon Eucalyptus: According to the label, this products should NOT be used on CHILDREN UNDER 3 YEARS.
  • Picaridin: AAP has not yet issued specific recommendations or opinion concerning the use of picaridin.
  • IR 3535: According to the label, IR 3535 can be used on infants over 6 months of age.

Always read label instructions when using repellents.

Can insect repellents be used by pregnant or nursing women?

Other than the routine precautions noted earlier, EPA does not have any additional precautions for using registered repellents on pregnant or lactating women. Consult your health care provider if you have questions.

Where can I get more information about repellents?

For more information about repellents, please consult:

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