Picaridin is a synthetic insect repellent that works as well as DEET against mosquitoes and ticks but without the greasy feel, strong smell, or risk of damaging your gear. Available in sprays, lotions, and wipes at concentrations ranging from 5% to 20%, it has become one of the most popular alternatives to DEET since its introduction to the U.S. market in 2005.
How Picaridin Repels Insects
Picaridin doesn’t kill insects. Instead, it scrambles their ability to find you. Mosquitoes locate humans primarily through sensors on their antennae that detect body heat, carbon dioxide, and skin odors. Picaridin stimulates sensory hairs on a mosquito’s antennae in a way that essentially jams those signals, preventing the insect from recognizing you as a host. The result is both repellent (insects move away from the chemical) and deterrent (insects that do land on treated skin won’t bite).
Interestingly, different mosquito species detect picaridin through different organs. Research on the yellow fever mosquito found that small sensory structures near the mouth played a key role in detecting the repellent, while a different species of malaria-carrying mosquito appeared to sense both prey and repellent through separate pathways. This partly explains why protection times can vary depending on where in the world you’re using it and which species are biting.
Picaridin vs. DEET
At equal concentrations, picaridin and DEET provide comparable protection against mosquitoes and ticks. A 20% picaridin product and a 20% DEET product will keep bugs away for roughly the same number of hours. The differences are practical rather than chemical.
DEET is a solvent. It can soften or dissolve plastics, synthetic fabrics, watch crystals, and certain coatings on sunglasses or fishing line. Picaridin is non-damaging to clothing and plastics, which makes it a better choice if you’re wearing technical outdoor gear, rain jackets, or carrying equipment with plastic components. Picaridin also has virtually no chemical odor and feels lighter on the skin, without the greasy residue DEET leaves behind. For people who have avoided repellent because they disliked the way DEET felt or smelled, picaridin solves both problems.
One area where DEET still has a longer track record is in extremely high-risk tropical environments. DEET has been studied for over 60 years, and formulations up to 30% remain the benchmark in malaria-endemic regions. That said, public health agencies list picaridin alongside DEET as an effective option for preventing mosquito-borne diseases like Zika, dengue, and West Nile virus.
Which Bugs It Works Against
Picaridin is effective against mosquitoes, ticks, biting flies, sand flies, gnats, and chiggers. At 20% concentration, most products provide 8 to 14 hours of mosquito protection and up to 8 hours of tick protection, though exact times depend on the formulation and conditions like sweating, water exposure, and wind.
Lower concentrations offer shorter protection windows. A 5% to 10% product may only last one to two hours, which is fine for a short walk but not for an all-day hike. If you’re heading into heavy mosquito or tick territory, choose a product labeled at 20% and reapply according to the directions on the label.
Safety for Children and Pregnancy
Picaridin is safe to use on children over 2 months old, making it one of the earliest-approved repellent options for infants. (By comparison, oil of lemon eucalyptus should not be used on children under 3 years old.) For young children, spray picaridin onto your own hands first, then apply it to the child’s exposed skin, avoiding the eyes, mouth, and hands, since kids tend to put their fingers in their mouths.
Major health organizations consider EPA-registered repellents, including picaridin, safe during pregnancy and breastfeeding when used as directed. The consensus is that the benefits of preventing mosquito-borne infections outweigh theoretical risks. Current data do not show an increased risk of birth defects from these products. If you’re breastfeeding, the main precaution is to avoid applying repellent to the nipple and areola before nursing.
Using Picaridin With Sunscreen
If you need both sun protection and bug protection, the CDC recommends applying sunscreen first, waiting about 10 minutes for it to absorb into the skin, then applying your picaridin repellent on top. This order matters because repellent needs to sit on the skin’s surface to work, while sunscreen needs to bind to the skin. Avoid combination sunscreen-repellent products. Sunscreen needs reapplication every two hours, while repellent lasts much longer, and reapplying the combo too often means overexposure to the repellent.
How to Apply It Effectively
Spray picaridin on all exposed skin, not just your arms. Mosquitoes are opportunistic and will find ankles, the backs of knees, necks, and ears. If using a spray, hold the can 6 to 8 inches from your skin and use a sweeping motion for even coverage. You can also spray it on clothing for an extra layer of protection, and unlike DEET, you won’t have to worry about it damaging the fabric.
Don’t apply picaridin under clothing, since there’s no benefit and it increases unnecessary skin absorption. After you come inside, wash treated skin with soap and water. If you’ve sprayed it on clothing, wash those items before wearing them again.
Reapplication depends on the concentration and your activity level. Swimming or heavy sweating will break down protection faster. If you notice bites starting up again, it’s time to reapply regardless of what the label’s time estimate says.
Choosing a Concentration
Picaridin products come in three general tiers. A 5% to 10% formula works for brief outdoor time: a backyard dinner, a short dog walk, or a trip to the playground. A 15% product covers moderate outdoor activity lasting a few hours. And a 20% product is what you want for extended time outdoors, camping, hiking in wooded areas, or traveling to regions with mosquito-borne diseases.
The concentration affects duration of protection, not strength. A 20% product doesn’t repel mosquitoes “harder” than a 10% product. It just keeps working for a longer window before you need to reapply. For most people spending a full day outside, 20% is the practical choice because it minimizes how often you need to stop and reapply.