DEET, Picaridin or Permethrin, the Right Repellent for Mosquitoes, Chiggers and Ticks
A Collin County summer evening brings mosquitoes at the patio, chiggers in the tall grass and ticks along the fence line, and the repellent aisle offers a dozen bottles. Here is which ingredients the EPA and CDC back, how DEET and picaridin compare, where permethrin goes, what works on chiggers and what is safe for children.
- The CDC backs 6 active ingredients, DEET, picaridin, IR3535, oil of lemon eucalyptus, PMD and 2-undecanone.
- DEET keeps mosquitoes off for 2 to 12 hours, depending on its strength.
- Permethrin goes on clothing and gear, never on skin.
- DEET and picaridin both repel chiggers as well as mosquitoes and ticks.
- Look for an EPA registration number on the label before you buy.
Which mosquito repellents actually work?
The ones registered with the EPA that contain one of 6 active ingredients. The CDC lists DEET, picaridin, IR3535, oil of lemon eucalyptus, para-menthane-diol (PMD) and 2-undecanone, and says that used as directed they are proven safe and effective. Look for the EPA registration number, written EPA Reg. No., on the label.
The EPA says that number means the company gave it technical information on how well the product works. The CDC page on preventing mosquito bites says the same 6 ingredients are safe even for pregnant and breastfeeding women when used as directed.
How well any of them works on a given night still varies. The EPA’s guide to using repellents names 4 things that change it: how much you sweat, getting wet, the air temperature and how attractive you are to mosquitoes and ticks, which differs from person to person. Our article on why mosquito bites swell covers that last part.
Is DEET or picaridin better?
Neither wins outright. Both are on the CDC’s list of proven ingredients, so pick by the protection time on the label. The EPA says DEET protects against mosquitoes for 2 to 12 hours depending on its strength. Picaridin, sold in the United States since 2005, repels mosquitoes, ticks and chiggers, says the National Pesticide Information Center.
DEET is the older of the two. The EPA’s DEET page says the U.S. Army developed it in 1946, the public has used it since 1957, and about one-third of Americans use it every year. It does not kill mosquitoes. It makes it hard for them to smell you.
The National Pesticide Information Center, run from Oregon State University, says picaridin was first made in the 1980s to resemble a natural compound in the plants that give us black pepper, and was widely used in Europe and Australia before it reached the United States. It says skin irritation from picaridin is very uncommon. None of these sources gives picaridin a protection time in hours, so read that on the label. Outside the United States it is sold as icaridin, the CDC notes.
How long does DEET last?
DEET lasts 2 to 12 hours against mosquitoes, depending on its strength. For ticks, the studies the EPA has on file give about 2 to 10 hours, again by the percentage of DEET. Products made for skin run from 5 to 99 percent DEET, so check the label for the protection time and reapply when it runs out.
By the EPA figures, the strength of a DEET product changes how long it protects. That makes the choice simple. A 30 minute walk at dusk needs less than a full Saturday clearing brush at the back of a Prosper or Celina lot. The EPA keeps a search tool on its repellent pages that sorts registered products by protection time and by mosquitoes, ticks or both.
Can you put permethrin on your skin?
No. Permethrin goes on clothing, shoes and gear, never on skin. The CDC says not to use permethrin products directly on skin, and that permethrin-treated clothing keeps protecting after multiple washings. Texas A&M AgriLife Extension says to spray it on clothing, let it dry before wearing, and combine it with DEET on your skin where chiggers are heavy.
Permethrin is an insecticide, the CDC says, that kills or repels mosquitoes. The EPA’s page on treated clothing says it is the only repellent used in factory-treated clothing, that only the skin under the treated cloth is protected, and that treated clothing should be washed separately.
Keep it away from the cat. The National Pesticide Information Center says cats are more sensitive to permethrin than dogs or people, because their bodies take a long time to break it down. It also says permethrin is highly toxic to fish and to bees, so spray clothing away from the pond and the flower beds.
What repellent works on chiggers?
DEET or picaridin on skin, and permethrin on clothing. Texas A&M AgriLife Extension says DEET protects against chiggers on exposed skin and around cuffs, waistbands and boot tops, and permethrin on clothing gives long-lasting protection. The National Pesticide Information Center says picaridin repels chiggers too, and Ohio State adds oil of lemon eucalyptus.
The Texas A&M AgriLife chigger guide says to combine permethrin-treated clothing with DEET on the skin where chiggers are heavy. It says sulfur powder on clothing may also help, and that plant-oil repellents may never have been tested on chiggers, so pick one only if its label says it repels chiggers.
Chiggers wait in tall grass and climb onto shoes, so the repellent matters most at the ankles, boot tops and waistband. Our articles on where chiggers wait in a Texas yard and how long chigger bites last cover the rest.
Is DEET safe for kids?
Yes for children 2 months and older, used as the label directs. The EPA sets no age or strength limit. The American Academy of Pediatrics is stricter, the National Pesticide Information Center says: no DEET under 2 months old, the lowest strength available, no more than once a day, and never on a child’s hands.
The CDC says not to use oil of lemon eucalyptus or PMD on children under 3, and not to put any repellent on a child’s hands, eyes, mouth, cuts or irritated skin. Spray it on your own hands first and rub it on the child’s face. The EPA says to keep repellents out of children’s reach and to wash a child’s treated skin and clothes with soap and water once you are back inside.
Do natural mosquito repellents work?
Two plant-based ingredients do. The CDC lists oil of lemon eucalyptus and 2-undecanone, both plant-derived, among its 6 proven repellent ingredients, as long as the product is registered with the EPA. Unregistered plant-oil sprays are a different matter. Texas A&M AgriLife Extension says plant-oil repellents may not have been tested on chiggers at all.
Look for the EPA registration number before trusting any natural label. A citronella plant on the patio is not a repellent you wear, as our article on plants that repel mosquitoes explains, and the day-biting tiger mosquito needs repellent in the afternoon as well as the evening, as our Asian tiger mosquito article says.
The repellents side by side
From the CDC, the EPA, the National Pesticide Information Center and Texas A&M AgriLife Extension.
| Ingredient | Where it goes | Mosquitoes and ticks | Chiggers | Worth knowing |
|---|---|---|---|---|
| DEET | Exposed skin and clothing | Yes, 2 to 12 hours for mosquitoes | Yes | No age limit from the EPA |
| Picaridin | Skin or clothing | Yes | Yes | Skin irritation very uncommon |
| Permethrin | Clothing and gear only | Yes, kills or repels | Yes | Never on skin, keep from cats |
| Oil of lemon eucalyptus | Skin, per the label | Yes for mosquitoes | Ohio State lists it, Texas A&M says check the label | Not on children under 3 |
Whatever the bottle, the EPA registration number is what tells you it was tested.
Five rules for using repellent the right way
- Read the label and use the amount it says. The EPA says too little may not work as well as you expect.
- Put sunscreen on first and repellent second, as the CDC advises.
- Spray only exposed skin and the outside of clothing, never under clothing or over cuts, and to do your face, spray your hands first and rub it on, as the EPA advises.
- Spray clothing with permethrin and let it dry fully before you wear it, as Texas A&M AgriLife says, and wash it apart from the rest of the laundry, as the EPA says.
- Wash treated skin with soap and water once you are back inside, as the EPA advises.
Repellent protects you, a yard treatment cuts the numbers
Repellent only covers the person wearing it. Pest Me Off is a family-owned, Texas-licensed pest control company working in McKinney, Plano, Frisco and Allen since 2014, and on a mosquito control visit a licensed applicator, never a subcontractor, treats the shaded foliage where adult mosquitoes wait and finds and drains the water where they breed.
The treatment is EPA-registered and pet-safe once it dries, in 1 to 2 hours, and the visits come every 3 weeks through the April to October season. For ticks and chiggers, our flea and tick control visit starts by confirming what is biting, and our chigger control page covers chiggers on their own.
Tired of spraying yourself just to sit on the patio? Same-day mosquito control in McKinney and the surrounding cities when you call before noon.
We treat the shaded plants where mosquitoes wait and drain the water where they breed, so you need less repellent in your own yard. Free inspection and estimate.
