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& Control PDF (254 

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Updated Information regarding Insect 

Repellents

Download PDF version formatted for print (32 KB/3 pages) 

Updated May 8, 2008!

Repellents are an important tool to assist people in protecting 

themselves from mosquito-borne diseases.

CDC recommends the use of products containing active ingredients which have 

been registered by the U.S. Environmental Protection Agency (EPA) for use as 

repellents applied to skin and clothing. EPA registration of repellent active 

ingredients indicates the materials have been reviewed and approved for efficacy 

and human safety when applied according to the instructions on the label. 

Repellents for use on skin and clothing:

CDC evaluation of information contained in peer-reviewed scientific literature and 

data available from EPA has identified several EPA registered products that provide 

repellent activity sufficient to help people avoid the bites of disease carrying 

mosquitoes. Products containing these active ingredients typically provide 

reasonably long-lasting protection: 

z DEET (Chemical Name: N,N-diethyl-m-toluamide or N,N-diethly-3-methylbenzamide) 

z Picaridin (KBR 3023, Chemical Name: 2-(2-hydroxyethyl)-1-

piperidinecarboxylic acid 1-methylpropyl ester ) 

z Oil of Lemon Eucalyptus* or PMD (Chemical Name: para-Menthane-3,8-

diol) the synthesized version of oil of lemon eucalyptus 

z IR3535 (Chemical Name: 3-[N-Butyl-N-acetyl]-aminopropionic acid, ethyl 

ester) 

EPA characterizes the active ingredients DEET and Picaridin as “conventional 

repellents” and Oil of Lemon Eucalyptus, PMD, and IR3535 as “biopesticide 

repellents”, which are derived from natural materials. For more information on 

repellent active ingredients see 

(http://www.epa.gov/pesticides/health/mosquitoes/ai_insectrp.htm). 

Published data indicate that repellent efficacy and duration of protection vary 

considerably among products and among mosquito species and are markedly 

affected by ambient temperature, amount of perspiration, exposure to water, 

abrasive removal, and other factors. 

In general, higher concentrations of active ingredient provide longer duration of 

protection, regardless of the active ingredient, although concentrations above 

~50% do not offer a marked increase in protection time. Products with <10% 

active ingredient may offer only limited protection, often from 1-2 hours. Products 

that offer sustained release or controlled release (micro-encapsulated) 

formulations, even with lower active ingredient concentrations, may provide longer 

protection times. Regardless of what product you use, if you start to get mosquito 

CDC: West Nile Virus - Updated Insect Repellent Page 1 of 3

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bites reapply the repellent according to the label instructions or remove yourself 

from the area with biting insects if possible. 

These recommendations are for domestic use in the United States where EPAregistered products are readily available. See CDC Travelers’ Health website for 

additional recommendations concerning protection from insects when traveling 

outside the United States. 

Repellents for use on clothing:

Certain products containing permethrin are recommended for use on clothing, 

shoes, bed nets, and camping gear, and are registered with EPA for this use. 

Permethrin is highly effective as an insecticide and as a repellent. Permethrintreated clothing repels and kills ticks, mosquitoes, and other arthropods and 

retains this effect after repeated laundering. The permethrin insecticide should be 

reapplied following the label instructions. Some commercial products are available 

pretreated with permethrin. 

EPA recommends the following precautions when using insect repellents:

z Apply repellents only to exposed skin and/or clothing (as directed on the 

product label.) Do not use repellents under clothing. 

z Never use repellents over cuts, wounds or irritated skin. 

z Do not apply to eyes or mouth, and apply sparingly around ears. When 

using sprays, do not spray directly on face—spray on hands first and then 

apply to face. 

z Do not allow children to handle the product. When using on children, apply 

to your own hands first and then put it on the child. You may not want to 

apply to children’s hands. 

z Use just enough repellent to cover exposed skin and/or clothing. Heavy 

application and saturation are generally unnecessary for effectiveness. If 

biting insects do not respond to a thin film of repellent, then apply a bit 

more. 

z After returning indoors, wash treated skin with soap and water or bathe. 

This is particularly important when repellents are used repeatedly in a day 

or on consecutive days. Also, wash treated clothing before wearing it again. 

(This precaution may vary with different repellents—check the product 

label.) 

z If you or your child get a rash or other bad reaction from an insect repellent, 

stop using the repellent, wash the repellent off with mild soap and water, 

and call a local poison control center for further guidance. If you go to a 

doctor because of the repellent, take the repellent with you to show the 

doctor. 

Note that the label for products containing oil of lemon eucalyptus specifies that 

they should not to be used on children under the age of three years. Other than 

those listed above, EPA does not recommend any additional precautions for using 

registered repellents on children or on pregnant or lactating women,. For additional 

information regarding the use of repellent on children, please see CDC’s Frequently 

Asked Questions about Repellent Use. 

[http://www.cdc.gov/ncidod/dvbid/westnile/qa/insect_repellent.htm] 

DEET-based repellents applied according to label instructions may be used along 

with a separate sunscreen. No data are available at this time regarding the use of 

other active repellent ingredients in combination with a sunscreen. 

See http://www.epa.gov/pesticides/health/mosquitoes/insectrp.htm for additional 

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information on using EPA-registered repellents. 

* Note: This recommendation refers to EPA-registered repellent products 

containing the active ingredient oil of lemon eucalyptus (or PMD). “Pure” oil of 

lemon eucalyptus (e.g. essential oil) has not received similar, validated testing for 

safety and efficacy, is not registered with EPA as an insect repellent, and is not 

covered by this CDC recommendation. 

References:

Barnard DR, Xue RD. Laboratory evaluation of mosquito repellents against Aedes 

albopictus, Culex nigripalpus, and Ochlerotatus triseriatus (Diptera: Culicidae). J 

Med Entomol. 2004;41(4):726-30. 

Barnard DR, et al. Repellency of IR3535, KBR3023, para-menthane-3,8-diol, and 

DEET to Black Salt March mosquitoes (Diptera: Culicidae) in the Everglades 

National Park. J Med Entomol. 2002; 39(6): 895-899 

Fradin MS, Day JF. Comparative efficacy of insect repellents against mosquito 

bites. N Engl J Med. 2002; 347(1):13-8. 

Thavara U et al. Laboratory and field evaluations of the insect repellents 3535 

(ethyl butyletylaminopropionate) and DEET against mosquito vectors in Thailiand. J 

of Am Mosq Cont Assoc. 2001, 17(3):190-195 

 

 

For more information, visit www.cdc.gov/westnile, or call CDC at 

800-CDC-INFO (English and Spanish) or 888-232-6348 (TTY).

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