Insect Repellent for Hiking and Backpacking
Treat boots, socks, and tents with 0.5% permethrin 24 to 48 hours before your trip, then apply an EPA-registered skin repellent in a thin film on exposed skin at the trailhead. On trail, walk the center of the path and reapply per the label. Afterward, shower within two hours and run dry clothes in a hot dryer for 10 minutes.
Why do hikers need a bite plan at all?
The CDC's Yellow Book names hiking and camping among the activities that bring people into close contact with ticks. That tracks: ticks live in grassy, brushy, or wooded areas, which describes most trail corridors, and they can be found in every U.S. state, though not all ticks spread the same germs.
The stakes are not abstract. Nearly half a million people are diagnosed and treated for a tickborne disease in the United States each year, and a 2021 CDC estimate based on insurance records puts Lyme disease alone at approximately 476,000 Americans annually. Reported cases of Lyme disease, anaplasmosis, babesiosis, and Powassan virus disease are concentrated in the Northeast, mid-Atlantic, and upper Midwest, with pockets of risk along the Pacific coast. Exposure can happen year-round, but ticks are most active in the warmer months, April through September.
Mosquitoes earn a spot in the plan too. They bite day and night and can spread germs that make you sick. West Nile virus is the leading cause of mosquito-borne disease in the contiguous United States; per the CDC, each year more than 1,300 people develop severe illness affecting the central nervous system and more than 130 die.
None of this needs to keep you home; it changes what you do the night before, at the trailhead, on the trail, and when you get back. Here is the whole day, in order.
What should you treat before you leave for the trailhead?
Gear comes first, and it starts at home. The CDC advises treating clothing and gear with products containing 0.5% permethrin, and it lists boots, pants, socks, and tents among the items that can be treated. You can also buy clothing and gear pre-treated. At that 0.5% concentration, permethrin-treated clothing repels and kills chiggers, mosquitoes, ticks, and other biting arthropods. Permethrin itself is an insecticide in the pyrethroid family, synthetic chemicals that act like natural extracts from the chrysanthemum flower.
Two rules govern the job. First, timing: treat clothing and gear 24 to 48 hours before you pack so everything has time to dry, and always follow the label instructions. Second, placement: permethrin should never be applied to skin, only to clothing, mosquito nets, or other fabrics as directed on the product label. Your skin gets a different product.
The treatment lasts. Permethrin-treated clothing remains protective through several washings, and treated materials keep their repellent and insecticidal activity through repeated launderings, though they need retreatment as described on the product label. The label also tells you to wash treated clothing separately from untreated clothing, and treated products are not to be applied to certain clothing such as underwear. We walk through the full gear-plus-skin routine in our permethrin and picaridin system guide.
What goes on your skin at the trailhead?
Exposed skin gets an EPA-registered repellent. The CDC recommends EPA-registered insect repellents containing DEET, picaridin, IR3535, oil of lemon eucalyptus, para-menthane-diol, or 2-undecanone, and says to check for an EPA registration number on the label. That number means the company provided EPA with technical information on the product's effectiveness.
Picaridin is the active we know best. It is a synthetic compound first made in the 1980s, modeled on piperine, a natural compound found in the plants used to produce black pepper. It works by repelling rather than killing; it appears to block mosquitoes from sensing their prey. It can be used on skin or clothing to repel mosquitoes, biting flies, ticks, fleas, and chiggers. For how protection windows play out in practice, see how long picaridin lasts.
Application is simpler than most people make it. A thin, even film over exposed skin is enough; heavy application and saturation are generally unnecessary for effectiveness. Exposed is the operative word: do not apply repellent on skin under clothing. And the EPA makes a point every hiker should memorize: permethrin-treated clothing protects only the skin it covers, so treat the rest of your exposed skin with a repellent labeled for use on human skin. That is the whole logic of the two-layer approach.
If the sun is out, order matters. The CDC says apply sunscreen first and insect repellent second. The Yellow Book adds that you should use separate products rather than a combination sunscreen-repellent, because sunscreen may need to be reapplied more often and in larger amounts than the repellent component.
Clothing does quiet work too. The CDC advises loose-fitting, long-sleeved shirts and pants for mosquitoes, and the Yellow Book recommends minimizing exposed skin with long sleeves, long pants, boots, and hats, tucking in your shirt, tucking pants into socks, and wearing closed shoes instead of sandals. Pants tucked into socks look ridiculous and reduce risk anyway.
One packing note, courtesy of the National Pesticide Information Center: DEET acts as a plasticizer and can damage certain rubber, plastic, vinyl, or elastic materials, including eyeglass frames and lenses, watch crystals, and certain synthetic fabrics. It does not damage natural fibers like cotton and wool. Whichever active you carry, check the product label for handling directions.
How do ticks actually get on you mid-hike?
Not the way most people picture. Ticks cannot fly or jump. They find hosts by detecting breath and body odor, or by sensing body heat, moisture, and vibrations, and many species wait for a host on the tips of grasses and shrubs in a position known as questing. Per the CDC, ticks even pick their waiting spot by identifying well-used paths.
A questing tick holds onto leaves and grass with its back legs and stretches its first pair of legs out, waiting. When you brush the spot where it sits, it climbs aboard. Some attach quickly; others wander, looking for places like the ear, or other areas where the skin is thinner.
This is why trail position matters. The CDC advises avoiding wooded and brushy areas with high grass and leaf litter and walking in the center of trails, and its Yellow Book repeats the advice for hikers specifically: stay in the center of hiking trails. The brushy shortcut is exactly where the waiting happens.
Meanwhile, your morning application is aging. The EPA notes that a repellent's effectiveness can vary with physical activity and perspiration, water exposure, air temperature, and how attractive you personally are to mosquitoes and ticks. The CDC's Yellow Book goes further: efficacy and duration of protection vary considerably among products and are markedly affected by ambient temperature, activity level, perspiration, water exposure, and being rubbed off during activity. So apply and reapply according to the label, using the amount the label indicates. If you start getting bitten, reapply, but never more often than the label allows.
What should you do back at camp or at home?
The hike ends; the checklist does not. Per the CDC, showering within two hours of coming indoors has been shown to reduce your risk of getting Lyme disease, may help wash off unattached ticks, and is a good opportunity to do a tick check.
Do the full-body check with a mirror, and be systematic about it: under the arms, in and around the ears, inside the belly button, behind the knees, in and around the hair, between the legs, and around the waist. If you find something and are not sure what it is, our tick identification guide can help. If one has attached, our tick removal guide walks through the steps.
Clothes go straight into the dryer: tumble drying on high heat for 10 minutes kills any ticks on dry clothing, and damp clothes may need more time. Then check the rest of the kit. Ticks can ride into your home on clothing, pets, and daypacks and attach to a person later, so examine pets, coats, and packs carefully. If a tick has attached, or you develop symptoms after a trip, talk to a clinician.
What does not work?
The trail community has its folk remedies, and the CDC's Yellow Book is blunt about them: eating vitamin B or garlic and wearing sound-emitting devices or repellent-impregnated wristbands are ineffective. More broadly, the effectiveness of non-EPA-registered repellents, including some natural repellents, is not known, which is why the CDC and EPA recommend using an EPA-registered insect repellent.
Where does Longsleeve fit in?
Longsleeve is an EPA-registered picaridin lotion (EPA Reg. No. 101457-1). It repels mosquitoes and ticks for up to 14 hours. Its approved label also states that it won't damage fishing lines, plastics, or other synthetic materials.
Frequently asked questions
Can I put permethrin on my skin?
No. The CDC's Yellow Book says permethrin should never be applied to skin, only to clothing, mosquito nets, or other fabrics as directed on the product label. It belongs on boots, pants, socks, and tents, applied 24 to 48 hours before you pack so everything can dry.
How often should I reapply repellent on a hike?
Follow the label. The EPA says to apply and reapply according to the label instructions, and the CDC advises that if you start getting bitten you should reapply, but never more often than the label allows. Perspiration, water exposure, and rub-off can all shorten protection.
Does sunscreen go on before or after insect repellent?
Sunscreen first, repellent second, per the CDC. The Yellow Book also advises using separate products rather than a combination sunscreen-repellent, because sunscreen may need to be reapplied more often and in larger amounts than the repellent component.
When is tick season for hikers?
Tick exposure can happen year-round, but ticks are most active during the warmer months, April through September. They can be found in every U.S. state, though not all ticks spread the same germs.
Do repellent wristbands or garlic work?
No. The CDC's Yellow Book lists eating vitamin B or garlic and wearing sound-emitting devices or repellent-impregnated wristbands as ineffective. The CDC and EPA recommend using an EPA-registered insect repellent instead.
Sources
- CDC, Preventing Tick Bites: https://www.cdc.gov/ticks/prevention/index.html
- CDC Yellow Book, Mosquitoes, Ticks, and Other Arthropods: https://www.cdc.gov/yellow-book/hcp/environmental-hazards-risks/mosquitoes-ticks-and-other-arthropods.html
- CDC, Tick Press Kit: https://www.cdc.gov/ticks/communication-resources/press-kit.html
- CDC, About Ticks: https://www.cdc.gov/ticks/about/index.html
- CDC, Preventing Mosquito Bites: https://www.cdc.gov/mosquitoes/prevention/index.html
- CDC, About West Nile Virus: https://www.cdc.gov/west-nile-virus/about/index.html
- EPA, Using Insect Repellents Safely and Effectively: https://www.epa.gov/insect-repellents/using-insect-repellents-safely-and-effectively
- EPA, Repellent-Treated Clothing: https://www.epa.gov/insect-repellents/repellent-treated-clothing
- NPIC, Picaridin General Fact Sheet: https://npic.orst.edu/factsheets/PicaridinGen.html
- NPIC, Permethrin General Fact Sheet: https://npic.orst.edu/factsheets/PermGen.html
- NPIC, DEET Technical Fact Sheet: https://npic.orst.edu/factsheets/archive/DEETtech.html
Last reviewed 2026-08-17 · every claim on this page is sourced above