Ask Dr. Hale ( Response excerpted from InfantRisk Center website - www.infantrisk.com)

Dear Dr. Hale,

I’m a breastfeeding mom.  I love the outdoors, but the mosquitos are terrible where I live.  Will it hurt my baby if I use insect repellant? Can I put insect repellant on my baby?

Worried Mom

Dear Worried Mom,

It’s officially summertime and along with the warm weather comes all types of insects that buzz, sting, and bite.  While the itchy aftermath is enough to keep most people guarded from insect bites, we must also remember that sometimes the situation doesn’t just end with a bump. Mosquitos and ticks can carry painful or even potentially fatal diseases, such as Lyme Disease, Malaria, and West Nile Virus, which wreak havoc long after the red bumps have disappeared. In order to protect yourself and your children, be sure to follow the CDC’s guidelines for the usage of insect repellents when participating in outdoor activities.

The CDC suggests individuals use an insect repellent that contains DEET or Picaridin (only for use on clothes not for skin). Studies conducted by the EPA have shown repellents with these ingredients to be of a greater efficacy and protect for a longer duration than others with similar intent. The concentration of ingredient found in the repellent will usually determine the extent of protection. Thus those products with a concentration of less than 10% are effective for about 1 to 2 hours, while those with greater concentrations provide longer protection. However, those with greater than 50% concentrations do not show considerably greater protection lengths despite increased chemical exposure, which is why many repellents with extremely high concentrations have been phased out of the market. So be aware of the concentration of active ingredient in your insect repellent, and use the correct concentration for your circumstances.

Many pregnant or breastfeeding moms worry about the safety of using an insect repellent that contains conventional ingredients, such as DEET. However, those fears can be put to rest. A study conducted in Thailand found that no adverse neurological, gastrointestinal, or dermatological effects were noted in the women exposed to therapeutic doses of DEET in their second and third trimester. Furthermore, even though measureable levels of DEET were found in the cord blood, no adverse effects on survival, growth, or development were observed in the infants, of mothers who used DEET, at birth or at one year of age.(1)Currently, there are no data on the effects of DEET on women in the first trimester, but its use is assumed safe.(2)Thus, the CDC heavily recommends that when outdoors both pregnant and breastfeeding women should use an effective insect repellent on exposed skin and wear appropriate clothing with long pants and long sleeves for protection.

CDC Recommendations for Usage of DEET on Adults (including pregnant and breastfeeding women):

  • Use enough repellent to cover exposed skin or clothing. Don't 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.)
  • Do not spray aerosol or pump products in enclosed areas. 
  • Do not spray aerosol or pump products directly on your face. Spray your hands, and then rub them carefully over the face, avoiding eyes and mouth.

When used appropriately, children over the age of two months can be protected from insect bites and the diseases that accompany them by using DEET related products. In fact, a study that used data collected from the American Association of Poison Control Centers found that children are no more sensitive to DEET products than adults are. Additionally, they found that children who had adverse reactions to DEET typically had less severe outcomes than adults that were similarly exposed to topical doses DEET.(3) Although there are no definitive studies suggesting absolute safety for children using DEET related products, the American Academy of Pediatrics recommends that DEET concentrations between 10% and 30% are equally as safe for children over two months of age. Thus, be sure to use an insect repellent on your child that corresponds to the time spent outdoors because the risks of adverse effects are far outweighed by the protection from insect-borne disease. In addition, use mosquito netting to protect children who are younger than two months of age.

CDC Recommendations for Usage of DEET on Children:

  • Only use repellants that have less than 30% DEET on children. 
  • When using repellent on a child, apply it to your own hands, and then rub them on your child. Avoid children's eyes and mouth and use it sparingly around their ears.
  • Do not apply repellent to children's hands. (Children may tend to put their hands in their mouths.) 
  • Do not allow young children to apply insect repellent to themselves; have an adult do it for them. 
  • Keep repellents out of reach of children. 
  • Do not apply repellent under clothing. If repellent is applied to clothing, wash treated clothing before wearing again. (May vary by product, check label for specific instructions.)

Remember that the duration of protection and the efficacy of insect repellents will vary based on the types of insects, the concentration of the product, the intensity of abrasive interactions, and the exposure to water. So be sure to read the instructions and only apply as needed. Also, insect repellents that are combined with sunscreens should not be used. These products require more applications to maintain the efficacy of the sunscreen and cause unnecessary exposure to chemicals found in insect repellents, like DEET, which do not require as frequent reapplication. As always, if you have further questions, talk with your physician or call the InfantRisk Center for recommendations at (806)-352-2519.

 Laura Muscianese MS1

Thomas W. Hale, Ph.D.

For more information/References:

 American Academy of Pediatrics: http://aapnews.aappublications.org/cgi/content/full/e200399v1

Center for Disease Control: http://www.cdc.gov/ncidod/dvbid/westnile/qa/insect_repellent.htm#kids

National Pesticide Information Center: http://npic.orst.edu/ingred/ptype/repel.html

1. McGready R, Hamilton KA, Simpson JA, Cho T, Luxemburger C, Edwards R, et al. Safety of the insect repellent N,N-diethyl-M-toluamide (DEET) in pregnancy. Am J Trop Med Hyg. 2001;65(4):285-9.

2. Koren G, Matsui D, Bailey B. DEET-based insect repellents: safety implications for children and pregnant and lactating women. Cmaj. 2003;169(3):209-12.

3. Bell JW, Veltri JC, Page BC. Human Exposures to N,N-diethyl-m-toluamide insect repellents reported to the American Association of Poison Control Centers 1993-1997. Int J Toxicol. 2002;21(5):341-52.