Updated: June 10, 2025
Today, we’re taking a look at one of the most widely used and researched ingredients to prevent insect bites: DEET.
Top Takeaways:
- DEET is a common and well-studied insect repellent. It’s EPA-registered and proven safe and effective when used correctly.
- DEET confuses insect sensors. This helps stop mosquitoes and ticks from finding and biting you.
- DEET is safe for most people. It’s approved for children over 2 months of age, including pregnant and nursing individuals.
What are insect repellents?
Insect repellents are products that help prevent, repel, or mitigate pests. These can be products that we apply to our skin or products like lanterns or candles that use a heating mechanism to disperse repellents.
This post will focus on products that we apply topically, such as a spray or lotion.
What are EPA-approved insect repellent ingredients?
Some commonly found EPA-registered active ingredients include:
- 2-undecanone
- Catnip oil
- DEET
- IR-3535
- Oil of Citronella
- Oil of Lemon Eucalyptus
- Picaridin
- q-Methane-3,8-diol (pmd)
The most commonly used ingredient in EPA-approved insect repellents is DEET, and we find it in more than 500 products.
What is DEET?
DEET is the term used for the chemical ingredient N,N-diethyl-meta-toluamide that can repel mosquitoes and ticks that may carry harmful diseases.
DEET works by interfering with the receptors on a mosquito’s antennae making it harder for it to detect our presence, therefore they’re unable to find us to bite us.
It’s been in use since the late 1940s and has been studied extensively. Research shows it’s safe and effective when used as directed.
Why use DEET rather than other EPA-registered ingredients?
The U.S. Centers for Disease Control and Prevention (CDC) recommends the use of DEET products because extensive research shows DEET is safe and highly effective at preventing mosquito and tick bites. It’s also the most commonly used EPA-registered ingredient in insect repellent products.
Using safe and effective DEET-containing insect repellent products helps prevent the spread of harmful insect-borne diseases like malaria, Zika, West Nile, Lyme Disease, and more. These diseases can cause severe illness, and the potential for contracting them decreases with proper preventive measures, including the use of insect repellent.
How much DEET should I use?
DEET comes in various concentrations, ranging from 4% to 100%. The concentration determines how long the repellent properties last, rather than how many bugs it will prevent from biting you. In other words, if you choose a product that contains a high concentration of DEET, you will not need to reapply it as frequently as a product that contains a low DEET concentration. The protection is the same. The duration is the difference.While there are high-concentration DEET products, research shows that there is little difference among products containing concentrations above 50% with respect to how long they remain effective.
The CDC recommends applying products with approximately 20% DEET concentration.
Is it safe to use? Even for children and those pregnant and nursing?
When used according to the directions, DEET is safe and even recommended for use by all populations who may be exposed to potentially disease-carrying mosquitoes and ticks.
The EPA’s data shows it’s safe for all children regardless of age. However, the American Academy of Pediatrics (AAP) recommends using DEET-containing products only on children older than two months of age.
We should never apply DEET-containing products directly to children’s hands or faces. Additionally, the AAP recommends that children wash off the DEET after it’s no longer needed.
Again, when used as directed, DEET-containing products are safe for pregnant and nursing mothers.
Can I have a reaction to DEET?
Although rare, DEET-containing products can cause skin irritation or reactions in some individuals. In that case, you should wash the area to remove any product, discontinue use, and contact a medical professional if it is severe.
The good news.
Spending time outdoors is good for your physical and mental health. With DEET-containing repellents, you can enjoy nature without worrying about bug bites or the diseases they may carry. When used correctly, DEET is a safe, effective, and essential tool for keeping you and your family protected.
If you have any questions about ingredients or ideas for a blog post, please send us an email or submit your idea to us at go.msu.edu/cris-idea.
Citations and further reading.
American Academy of Pediatrics. Follow safety precautions when using DEET on children. AAP News. https://publications.aap.org/aapnews/article/22/5/200399/20092/Follow-safety-precautions-when-using-DEET-on
American Chemistry Council. What you want to know about insect repellent and chemical safety. ChemicalSafetyFacts.org. https://www.chemicalsafetyfacts.org/health-and-safety/what-you-want-to-know-about-insect-repellent-and-chemical-safety/
National Pesticide Information Center. DEET technical fact sheet. Oregon State University. https://npic.orst.edu/factsheets/archive/DEETtech.html
Norris, E. J., & Coats, J. R. (2015). Current Opinion in Insect Science, 10, 71–76. The enigmatic reception of DEET — the gold standard of insect repellents. https://doi.org/10.1016/j.cois.2014.10.007
U.S. Department of Health & Human Services. Centers for Disease Control and Prevention. Mosquitoes, ticks & other arthropods. https://www.cdc.gov/yellow-book/hcp/environmental-hazards-risks/mosquitoes-ticks-and-other-arthropods.html
U.S. Environmental Protection Agency. DEET (N,N-diethyl-m-toluamide). https://www.epa.gov/insect-repellents/deet
U.S. Environmental Protection Agency. Skin-applied repellent ingredients. https://www.epa.gov/insect-repellents/skin-applied-repellent-ingredients
U.S. Environmental Protection Agency. What is an insect repellent? https://www.epa.gov/insect-repellents/what-insect-repellent