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DEET vs Picaridin

The same eleven questions, side by side, each answer in the agency's words. No verdict from us: we sell a product built on one of these actives, so the agencies do the talking.

DEETN,N-diethyl-meta-toluamide
Picaridinicaridin, KBR 3023

Per EPA's tool

DEET

Registered; 505 products in EPA's tool; 2 to 12 h mosquitoes, 2 to 10 h ticks.

Picaridin

Registered; 55 products in EPA's tool; 3 to 14 h mosquitoes, 5 to 14 h ticks.

What is it, and where does it come from?

DEET

EPA says DEET, made for skin, works by making it hard for biting bugs to smell us.

Source and detail: EPA

DEET, N,N-diethyl-meta-toluamide, is what EPA's DEET page calls the active ingredient in many repellent products, designed for direct application to people's skin. EPA says it was developed by the U.S. Army in 1946 and registered for use by the general public in 1957, and that rather than killing biting bugs it works by making it hard for them to smell us.

DEET (chemical name, N,N-diethyl-meta-toluamide) is the active ingredient in many repellent products. It is widely used to repel biting pests such as mosquitoes and ticks. Every year, an estimated one-third of the U.S. population use DEET to protect them from mosquito-borne illnesses like West Nile Virus, the Zika virus or malaria and tick-borne illnesses like Lyme disease and Rocky Mountain spotted fever.

EPA, DEET (epa.gov/insect-repellents/deet), fetched 2026-09-22

DEET is designed for direct application to people's skin to repel insects. Rather than killing them, DEET works by making it hard for these biting bugs to smell us. After it was developed by the U.S. Army in 1946, DEET was registered for use by the general public in 1957. Approximately 120 products containing DEET are currently registered with EPA by about 30 different companies.

EPA, DEET (epa.gov/insect-repellents/deet), fetched 2026-09-22
Picaridin

A human-made compound, NPIC says, widely used in Europe and Australia, available in the U.S. only since 2005.

Source and detail: NPIC

Picaridin is a human-made compound first made in the 1980s; NPIC's picaridin fact sheet says it was made to resemble the natural compound piperine, found in the group of plants used to produce black pepper. NPIC says it was widely used as an insect repellent in Europe and Australia but has only been available in the United States since 2005.

Picaridin repels insects, ticks and chiggers. It is a human-made (synthetic) compound first made in the 1980s. It was made to resemble the natural compound piperine, which is found in the group of plants that are used to produce black pepper.

NPIC, Picaridin General Fact Sheet

Picaridin has been widely used as an insect repellent in Europe and Australia, but has only been available in the United States since 2005.

NPIC, Picaridin General Fact Sheet

How does EPA treat it?

DEET

Registered, about 120 products per EPA; its 1998 review found repellents containing DEET present no health concern.

Source and detail: EPA

Registered: EPA's DEET page says approximately 120 products containing DEET are registered with EPA by about 30 companies. EPA's 1998 reregistration decision concluded that insect repellents containing DEET do not present a health concern; its registration review risk assessment found no risks of concern because no toxic effects have been identified when it is used as a dermally applied insect repellent, with a final decision waiting on Endocrine Disruptor Screening.

DEET is designed for direct application to people's skin to repel insects. Rather than killing them, DEET works by making it hard for these biting bugs to smell us. After it was developed by the U.S. Army in 1946, DEET was registered for use by the general public in 1957. Approximately 120 products containing DEET are currently registered with EPA by about 30 different companies.

EPA, DEET (epa.gov/insect-repellents/deet), fetched 2026-09-22

After completing a comprehensive re-assessment of DEET, we concluded that insect repellents containing DEET do not present a health concern. Consumers are advised to read and follow label directions when using any pesticide product, including insect repellents. Based on extensive toxicity testing, we believe that the normal use of DEET does not present a health concern to the general population, including children. We completed this review and issued a reregistration decision (called a RED) in 1998.

EPA, DEET (epa.gov/insect-repellents/deet), fetched 2026-09-22

The human health risk assessment concluded that there are no risks of concern because no toxic effects have been identified when used as a dermally applied insect repellent, and there is no dietary or occupational exposure for DEET. However, a Final Decision on the DEET registration review case will occur only after the EPA has completed an Endocrine Disruptor Screening under FFDCA section 408(p).

EPA, DEET (epa.gov/insect-repellents/deet), fetched 2026-09-22
Picaridin

Registered since 2001; EPA's 2005 fact sheet says normal use does not present a health concern.

Source and detail: EPA

Registered: EPA's 2005 picaridin fact sheet gives 2001 as the year of initial registration. The same fact sheet says picaridin generally is of low acute toxicity and that, based on the available toxicological data, the Agency believes normal use of picaridin does not present a health concern to the general U.S. population.

Year of Initial Registration: 2001

EPA, New Pesticide Fact Sheet: Picaridin, May 2005

Picaridin generally is of low acute toxicity, and based on the available toxicological data, the Agency believes that the normal use of Picaridin does not present a health concern to the general U.S. population

EPA, New Pesticide Fact Sheet: Picaridin, May 2005

What strengths are registered, and does strength change protection?

DEET

EPA registers 5 to 99%; CDC says higher concentrations generally protect longer, with DEET peaking near 50%.

Source and detail: CDC Yellow Book, EPA

EPA's DEET page says formulations registered for direct application to human skin contain from 5 to 99 percent DEET. CDC's Yellow Book says higher concentrations generally provide longer protection regardless of the active ingredient, and that studies suggest DEET efficacy tends to peak at approximately 50 percent, with concentrations above that not offering a marked increase in protection time against mosquitoes.

Products containing DEET currently are available to the public in a variety of liquids, lotions, sprays, and impregnated materials (e.g., towelettes, roll on). Formulations registered for direct application to human skin contain from 5 to 99% DEET.

EPA, DEET (epa.gov/insect-repellents/deet), fetched 2026-09-22

In general, higher concentrations of active ingredients provide longer duration of protection, regardless of the active ingredient. Products with <10% active ingredient might offer only limited protection, often 1-2 hours. Products that offer sustained-release or controlled-release (microencapsulated) formulations, even with lower active ingredient concentrations, might provide longer protection times. Studies suggest that DEET efficacy tends to peak at a concentration of approximately 50% and that concentrations above that do not offer a marked increase in protection time against mosquitoes.

CDC Yellow Book, Mosquitoes, Ticks, and Other Arthropods (Wayback Machine capture 2026-09-19)
Picaridin

EPA lists products at 5, 5.75, 7, 10 and 20%; CDC says higher concentrations generally protect longer.

Source and detail: CDC Yellow Book, EPA

No EPA page we read states a picaridin percentage range in prose; EPA's 2005 picaridin fact sheet lists registered formulations at 5 and 7 percent (pump sprays), 10 percent (aerosol) and 5.75 percent (towelette wipes), and EPA's repellent search tool lists 20 percent picaridin lotion, spray and wipe products. CDC's Yellow Book says higher concentrations of active ingredients generally provide longer protection, regardless of the active ingredient.

Registered: 96.8% a.i. Technical; 5% & 7% pump sprays; 10% aerosol spray and 5.75% towelette wipes

EPA, New Pesticide Fact Sheet: Picaridin, May 2005

Sawyer Picaridin Insect Repellent Lotion | 14 | 14 | Picaridin | 20 | Sawyer Products | 39967-50-58188

EPA, Find the Repellent that is Right for You, search results for picaridin, cfpub.epa.gov/oppref/insect_s

Ranger Ready Repellents Tick + Insect Spray | 12 | 12 | Picaridin | 20 | The PIC20 Group, LLC | 93221-1

EPA, Find the Repellent that is Right for You, search results for picaridin, cfpub.epa.gov/oppref/insect_s

Natrapel 8 Hour Insect Repellent Wipes | 8 | 8 | Picaridin | 20 | Tender Corp. | 56575-14

EPA, Find the Repellent that is Right for You, search results for picaridin, cfpub.epa.gov/oppref/insect_s

In general, higher concentrations of active ingredients provide longer duration of protection, regardless of the active ingredient. Products with <10% active ingredient might offer only limited protection, often 1-2 hours. Products that offer sustained-release or controlled-release (microencapsulated) formulations, even with lower active ingredient concentrations, might provide longer protection times. Studies suggest that DEET efficacy tends to peak at a concentration of approximately 50% and that concentrations above that do not offer a marked increase in protection time against mosquitoes.

CDC Yellow Book, Mosquitoes, Ticks, and Other Arthropods (Wayback Machine capture 2026-09-19)

How long does EPA say it protects?

DEET

EPA says 2 to 12 hours for mosquitoes and 2 to 10 for ticks, depending on the percentage.

Source and detail: EPA, U.S. EPA

EPA's DEET page says studies in its database indicate DEET repels ticks for about two to ten hours and mosquitoes from two to twelve hours, depending on the percentage of DEET in the product. In EPA's repellent search tool, Ben's 100 Insect Repellent, EPA Reg. No. 56575-7, at 98.11 percent DEET, lists 10 hours for mosquitoes and 10 for ticks. EPA says protection times vary because testing conditions differ, and that the tool's database was last updated in June 2019.

Studies in EPA's database indicate that DEET repels ticks for about two to ten hours, and mosquitoes from two to twelve hours depending on the percentage of DEET in the product.

EPA, DEET (epa.gov/insect-repellents/deet), fetched 2026-09-22

Ben's 100 Insect Repellent | 10 | 10 | DEET | 98.11 | Tender Corp. | 56575-7

EPA, Find the Repellent that is Right for You, search results for DEET, cfpub.epa.gov/oppref/insect_s

While this technical information is based on scientific testing guidelines and approved study methods, there are variations in the resulting protection times because of differences in the testing conditions.

EPA, Find the Repellent that is Right for You

Any products listed are for informational purposes only. Inclusion of a product listed/referenced is not an endorsement. * EPA and the U.S. Government do not endorse any product or service. * The information in this database was last updated in June 2019.

U.S. EPA, Find the Repellent that is Right for You
Picaridin

EPA's tool lists one 20% lotion at 14 hours, a spray at 12, wipes at 8.

Source and detail: EPA, U.S. EPA

EPA's repellent search tool lists 20 percent picaridin products by form. Sawyer Picaridin Insect Repellent Lotion, EPA Reg. No. 39967-50-58188, lists 14 hours for mosquitoes and ticks; Ranger Ready Repellents Tick + Insect Spray, EPA Reg. No. 93221-1, lists 12 hours, and Natrapel 8 Hour Insect Repellent Wipes, EPA Reg. No. 56575-14, lists 8. EPA says protection times vary because testing conditions differ, and that the tool's database was last updated in June 2019.

Sawyer Picaridin Insect Repellent Lotion | 14 | 14 | Picaridin | 20 | Sawyer Products | 39967-50-58188

EPA, Find the Repellent that is Right for You, search results for picaridin, cfpub.epa.gov/oppref/insect_s

Ranger Ready Repellents Tick + Insect Spray | 12 | 12 | Picaridin | 20 | The PIC20 Group, LLC | 93221-1

EPA, Find the Repellent that is Right for You, search results for picaridin, cfpub.epa.gov/oppref/insect_s

Natrapel 8 Hour Insect Repellent Wipes | 8 | 8 | Picaridin | 20 | Tender Corp. | 56575-14

EPA, Find the Repellent that is Right for You, search results for picaridin, cfpub.epa.gov/oppref/insect_s

While this technical information is based on scientific testing guidelines and approved study methods, there are variations in the resulting protection times because of differences in the testing conditions.

EPA, Find the Repellent that is Right for You

Any products listed are for informational purposes only. Inclusion of a product listed/referenced is not an endorsement. * EPA and the U.S. Government do not endorse any product or service. * The information in this database was last updated in June 2019.

U.S. EPA, Find the Repellent that is Right for You

Which pests do accepted labels name, and what does CDC say those pests carry?

DEET

A 15% label names mosquitoes, gnats, no-see-ums, biting flies, ticks, chiggers and fleas.

Source and detail: EPA notification label

The accepted label for a 15 percent DEET aerosol, EPA Reg. No. 4822-380, claims protection from mosquitoes, gnats, no-see-ums, biting flies, ticks, chiggers and fleas. On ticks, the label's exact wording is "including ticks that may cause Lyme disease."

EFFECTIVE PROTECTION from Mosquitoes, Gnats, No-See-Ums, Biting Flies, Ticks (including ticks that may cause Lyme disease), Chiggers and Fleas

EPA notification label, OFF! Insect Repellent II, EPA Reg. No. 4822-380, 15% DEET aerosol, November 13, 2009
Picaridin

A 20% label names mosquitoes, ticks, biting, stable, black and sand flies, gnats, chiggers and Scottish biting midges.

Source and detail: EPA stamped master label

The master label for a 20 percent picaridin spray, EPA Reg. No. 93221-1, claims 12 hour protection from ticks and mosquitoes and up to 8 hours against biting flies, stable flies, black flies, gnats, chiggers, sand flies and Scottish biting midges. The label's bracketed wording on disease is "mosquitoes that may transmit West Nile Virus, Chikungunya, Dengue [Fever], and Zika [Virus] and ticks carrying Lyme disease and tick borne encephalitis."

[Long-lasting, 12 hour effective protection from ticks and mosquitoes including mosquitoes that may transmit West Nile Virus, Chikungunya, Dengue [Fever], and Zika [Virus] and ticks carrying Lyme disease and tick borne encephalitis.] [Repels biting flies, stable flies, black flies, gnats, chiggers, sand flies, and Scottish biting midges for up to 8 hours.]

EPA stamped master label, Ranger Ready Repellents Tick + Insect Spray, EPA Reg. No. 93221-1, issued January 9, 2018

Picaridin ……………………………………………………………………….……20.00%

EPA stamped master label, Ranger Ready Repellents Tick + Insect Spray, EPA Reg. No. 93221-1, issued January 9, 2018

What do the agencies say about children?

DEET

No age limit, EPA and CDC say, and EPA sets no percentage limit for children.

Source and detail: CDC Yellow Book, EPA

EPA's DEET page states that DEET "is approved for use on children with no age restriction," and that there is no restriction on the percentage of DEET in a product for use on children, since registration tests showed no difference in effects between young and adult animals. CDC's Yellow Book says insect repellents containing DEET, picaridin, IR3535 and 2-undecanone can be used on children without age restriction.

DEET is approved for use on children with no age restriction. There is no restriction on the percentage of DEET in the product for use on children, since data do not show any difference in effects between young animals and adult animals in tests done for product registration.

EPA, DEET (epa.gov/insect-repellents/deet), fetched 2026-09-22

Insect repellents containing DEET, picaridin, IR3535, and 2-undecanone can be used on children without age restriction

CDC Yellow Book, Mosquitoes, Ticks, and Other Arthropods (Wayback Machine capture 2026-09-19)
Picaridin

No age limit, CDC says; one label's own wording says children 1 year and older.

Source and detail: CDC Yellow Book, EPA stamped master label

CDC's Yellow Book says insect repellents containing DEET, picaridin, IR3535 and 2-undecanone can be used on children without age restriction. The accepted master label for a 20 percent picaridin spray, EPA Reg. No. 93221-1, carries the optional bracketed line "Suitable for every day use on adults and children 1 year and older," one product's wording rather than an agency statement.

Insect repellents containing DEET, picaridin, IR3535, and 2-undecanone can be used on children without age restriction

CDC Yellow Book, Mosquitoes, Ticks, and Other Arthropods (Wayback Machine capture 2026-09-19)

[Suitable for every day use on adults and children 1 year and older]

EPA stamped master label, Ranger Ready Repellents Tick + Insect Spray, EPA Reg. No. 93221-1, issued January 9, 2018

Picaridin ……………………………………………………………………….……20.00%

EPA stamped master label, Ranger Ready Repellents Tick + Insect Spray, EPA Reg. No. 93221-1, issued January 9, 2018

What do CDC and WHO say about pregnancy?

DEET

CDC lists it for pregnant and breastfeeding women; one 897-woman trial found no adverse effects to one year.

Source and detail: CDC, McGready R

CDC's Preventing Mosquito Bites page lists DEET among the active ingredients it names, and says that when used as directed, EPA-registered insect repellents are "proven safe and effective, even for pregnant and breastfeeding women." McGready 2001, a double-blind randomized trial of 897 women, found no adverse neurologic, gastrointestinal or dermatologic effects from daily DEET in the second and third trimesters, and none on survival, growth or development at birth or one year.

Use EPA-registered insect repellents with one of the following active ingredients. When used as directed, EPA-registered insect repellents are proven safe and effective, even for pregnant and breastfeeding women.

CDC, Preventing Mosquito Bites (Wayback Machine capture 2026-09-16)

When used as directed, EPA-registered insect repellents are proven safe and effective, even for pregnant and breastfeeding women. DEET Picaridin (known as KBR 3023 and icaridin outside the United States)

CDC, Preventing Mosquito Bites (Wayback Machine capture 2026-09-16)

The safety of daily application of N, N-diethyl-m-toluamide (DEET) (1.7 g of DEET/day) in the second and third trimesters of pregnancy was assessed as part of a double-blind, randomized, therapeutic trial of insect repellents for the prevention of malaria in pregnancy (n = 897). No adverse neurologic, gastrointestinal, or dermatologic effects were observed for women who applied a median total dose of 214.2 g of DEET per pregnancy (range = 0-345.1 g).

McGready R, et al. Safety of the insect repellent N,N-diethyl-M-toluamide (DEET) in pregnancy. Am J Trop Med Hyg. 2001 Oct;65(4):285-9. PMID 11693870

DEET crossed the placenta and was detected in 8% (95% confidence interval = 2.6-18.2) of cord blood samples from a randomly selected subgroup of DEET users (n = 50). No adverse effects on survival, growth, or development at birth, or at one year, were found. This is the first study to document the safety of DEET applied regularly in the second and third trimesters of pregnancy.

McGready R, et al. Am J Trop Med Hyg. 2001 Oct;65(4):285-9. PMID 11693870
Picaridin

CDC lists it for pregnant and breastfeeding women; NPIC found no human data on reproductive effects.

Source and detail: CDC, NPIC

CDC's Preventing Mosquito Bites page lists picaridin among the active ingredients it names, and says that when used as directed, EPA-registered insect repellents are "proven safe and effective, even for pregnant and breastfeeding women." NPIC's picaridin technical fact sheet states that no human data were found on the teratogenic or reproductive effects of picaridin.

When used as directed, EPA-registered insect repellents are proven safe and effective, even for pregnant and breastfeeding women. DEET Picaridin (known as KBR 3023 and icaridin outside the United States)

CDC, Preventing Mosquito Bites (Wayback Machine capture 2026-09-16)

Use EPA-registered insect repellents with one of the following active ingredients. When used as directed, EPA-registered insect repellents are proven safe and effective, even for pregnant and breastfeeding women.

CDC, Preventing Mosquito Bites (Wayback Machine capture 2026-09-16)

No human data were found on the teratogenic or reproductive effects of picaridin.

NPIC, Picaridin Technical Fact Sheet (archived)

What do NPIC and EPA report about absorption and toxicity?

DEET

NPIC says a small amount absorbs through skin; EPA calls it generally low in acute toxicity.

Source and detail: EPA, NPIC

NPIC says a small amount of DEET applied to skin is taken into the body, more when alcohol is also on the skin. EPA's 1998 R.E.D. FACTS sheet calls DEET generally of low acute toxicity and a Group D carcinogen, not classifiable as a human carcinogen. EPA's 1998 reregistration decision counted 14 seizure cases since 1960, including four deaths, potentially related to DEET: an observed incidence of about one recognized seizure per 100 million users each year.

When DEET was applied to the skin of volunteers by researchers, they found that a small amount of the DEET was taken into the body through the skin. When DEET and alcohol are applied to the skin, more DEET is taken into the skin compared with DEET alone. Drinking alcohol may also cause more DEET to be absorbed through the skin. Sunscreen products that contain DEET may cause more DEET to be taken into the body through the skin.

NPIC, DEET General Fact Sheet

DEET generally is of low acute toxicity, and, based on the available toxicological data, the Agency believes that the normal use of DEET does not present a health concern to the general U.S. population (the Agency's human risk assessment has identified no toxicologically significant effects in animal studies.) DEET has been classified as a Group D carcinogen (not classifiable as a human carcinogen.)

EPA, R.E.D. FACTS: DEET, EPA-738-F-95-010, April 1998

In summary, since 1960, there have been 14 cases of seizure, including four deaths, potentially related to DEET exposure, for which other more likely causes have not been identified. An additional 32 cases of seizure reported to the national DEET registry are currently under review.

EPA, Reregistration Eligibility Decision (RED) DEET, EPA738-R-98-010, approved April 13, 1998

people using DEET each year, the observed incidence of recognized seizures is about one per 100 million users.

EPA, Reregistration Eligibility Decision (RED) DEET, EPA738-R-98-010, approved April 13, 1998
Picaridin

NPIC says under 6% absorbs through human skin; EPA calls it low in acute toxicity.

Source and detail: EPA, NPIC

NPIC says 60 percent of picaridin applied to rat skin went through it, while in humans less than 6 percent was absorbed; both excrete almost all in urine within a day. EPA's 2005 fact sheet says technical grade picaridin has low acute oral, dermal and inhalation toxicity, Toxicity Category IV for acute inhalation toxicity and primary dermal irritation, and Category III for acute oral and acute dermal toxicity and primary eye irritation.

When researchers applied picaridin to the skin of rats, 60% of it went through the skin. In humans, less than 6% of the picaridin applied to skin was absorbed. Picaridin may be broken down once it is in the body. Rats and humans excrete almost all of it in their urine within a day of exposure.

NPIC, Picaridin General Fact Sheet

Technical grade Picaridin has low acute oral, dermal and inhalation toxicity. It is classified as Toxicity Category IV for acute inhalation toxicity and primary dermal irritation and Toxicity Category III for acute oral, acute dermal and primary eye irritation.

EPA, New Pesticide Fact Sheet: Picaridin, May 2005

Does it damage plastics, fabrics or gear?

DEET

NPIC says it can damage certain plastics, rubber, vinyl and synthetics; a label spares nylon, cotton and wool.

Source and detail: EPA amended reregistration label, NPIC

NPIC's DEET technical fact sheet calls DEET a plasticizer that can damage certain rubber, plastic, vinyl or elastic materials, including contact lenses, eyeglass frames and lenses, watch crystals, combs, painted and varnished surfaces, and certain synthetic or treated fabrics. The accepted label for a 10 percent DEET product, EPA Reg. No. 121-53, says it will not damage nylon, cotton or wool.

DEET is a plasticizer and can damage certain rubber, plastic, vinyl, or elastic materials such as contact lenses, eyeglass frames and lenses, watch crystals, combs, painted and varnished surfaces, and certain synthetic or treated fabrics.

NPIC, DEET Technical Fact Sheet (archived)

Will not damage nylon, cotton, or wool.

EPA amended reregistration label, Cutter Insect Repellent #10GE, EPA Reg. No. 121-53, 10% DEET, March 18, 2009
Picaridin

Two labels claim no harm to plastics, fishing line, fabric and gear; no agency statement found.

Source and detail: EPA stamped label, EPA stamped master label

Two accepted 20 percent picaridin labels carry no-damage claims: EPA Reg. No. 93221-1, bracketed, "Won't Damage Fishing Lines, Plastics, or other Synthetic Materials"; EPA Reg. No. 54287-22, "Will [Does] not harm gear and equipment" and "Will [Does] not harm plastics and fabric."

What do the agencies say about pets?

DEET

EPA lists cats, dogs and horses as use sites; nothing on pets unless the label says so.

Source and detail: EPA, NPIC

EPA's 1998 R.E.D. FACTS sheet lists cats, dogs, horses and pet living and sleeping quarters among DEET's use sites. EPA tells consumers not to use any product on pets unless the label clearly states it is for animals. NPIC says reports of pets exposed to DEET in amounts that would make them sick are rare; overexposed pets have shown vomiting, shaking, excitement, lack of coordination and seizures.

N,N-diethyl-meta-toluamide (DEET) is an insect repellent used in households/domestic dwellings, on the human body and clothing being worn, on cats, dogs, horses and pet living/sleeping quarters. There are no food uses.

EPA, R.E.D. FACTS: DEET, EPA-738-F-95-010, April 1998

Do not use any product on pets or other animals unless the label clearly states it is for animals.

EPA, Using Insect Repellents Safely and Effectively

Reports of pets being exposed to DEET in amounts that would make them sick are rare. Pets that have been overexposed to DEET have shown varying effects, including vomiting, shaking, excitement, lack of coordination, and seizures.

NPIC, DEET General Fact Sheet
Picaridin

Only EPA's general rule applies: nothing on pets unless the label says so.

Source and detail: EPA

No agency or label we read covers picaridin use on pets. EPA tells consumers not to use any product on pets or other animals unless the label clearly states it is for animals.

Do not use any product on pets or other animals unless the label clearly states it is for animals.

EPA, Using Insect Repellents Safely and Effectively

Which studies are on the record?

DEET

One trial found 20% DEET and 20% picaridin performed equally, with 97.4% protection over five hours.

Source and detail: Carroll JF, Van Roey K

Van Roey 2014 (PLoS Neglected Tropical Diseases) reported an overall five-hour protection rate of 97.4 percent, with picaridin 20 percent performing equally well as DEET 20 percent. Carroll 2010 (Journal of Medical Entomology) found formulations of deet, picaridin and IR3535 at 20 percent or more active ingredient highly effective against lone star ticks over 12 hours, with fewer than 10 percent of ticks crossing the treatment bands.

Based on a total of 4996 mosquitoes collected on negative control persons, the overall five hour protection rate was 97.4% [95%CI: 97.1-97.8%], not decreasing over time. Picaridin 20% performed equally well as DEET 20% and better than picaridin 10%.

Van Roey K, et al. Field evaluation of picaridin repellents reveals differences in repellent sensitivity between Southeast Asian vectors of malaria and arboviruses. PLoS Negl Trop Dis. 2014 Dec 18;8(12):e3326. PMID 25522134

Formulations containing > or = 20% active ingredient were highly effective, with <10% of the ticks crossing through the treatment bands for any challenge during the 12 h. At least 40% of ticks exposed to any formulation for any challenge fell or crawled off the volunteers.

Carroll JF, Benante JP, Kramer M, Lohmeyer KH, Lawrence K. Formulations of deet, picaridin, and IR3535 applied to skin repel nymphs of the lone star tick (Acari: Ixodidae) for 12 hours. J Med Entomol. 2010 Jul;47(4):699-704. PMID 20695288

There was no difference in effectiveness between the 20% spray and 20% lotion formulations of picaridin. The 10% IR3535 lotion was significantly less effective than the formulations with higher concentrations of repellent. In the formulations tested, deet, picaridin, and IR3535 provided lasting protection against A. americanum.

Carroll JF, et al. J Med Entomol. 2010 Jul;47(4):699-704. PMID 20695288
Picaridin

One trial found 20% picaridin and 20% DEET performed equally, with 97.4% protection over five hours.

Source and detail: Carroll JF, Van Roey K

Van Roey 2014 (PLoS Neglected Tropical Diseases) reported an overall five-hour protection rate of 97.4 percent, with picaridin 20 percent performing equally well as DEET 20 percent. Carroll 2010 (Journal of Medical Entomology) found no difference in effectiveness between the 20 percent spray and lotion formulations of picaridin, and concluded that deet, picaridin and IR3535 provided lasting protection against lone star ticks as tested.

Based on a total of 4996 mosquitoes collected on negative control persons, the overall five hour protection rate was 97.4% [95%CI: 97.1-97.8%], not decreasing over time. Picaridin 20% performed equally well as DEET 20% and better than picaridin 10%.

Van Roey K, et al. PLoS Negl Trop Dis. 2014 Dec 18;8(12):e3326. PMID 25522134

There was no difference in effectiveness between the 20% spray and 20% lotion formulations of picaridin. The 10% IR3535 lotion was significantly less effective than the formulations with higher concentrations of repellent. In the formulations tested, deet, picaridin, and IR3535 provided lasting protection against A. americanum.

Carroll JF, et al. J Med Entomol. 2010 Jul;47(4):699-704. PMID 20695288

Sources on this page.

20 sources. Every quote was fetched on or before 2026-09-22 and is stored with the page. Last reviewed 2026-09-22. All ten actives.

  1. EPA, DEET (epa.gov/insect-repellents/deet), fetched 2026-09-22. https://www.epa.gov/insect-repellents/deet
  2. CDC Yellow Book, Mosquitoes, Ticks, and Other Arthropods (Wayback Machine capture 2026-09-19). https://www.cdc.gov/yellow-book/hcp/environmental-hazards-risks/mosquitoes-ticks-and-other-arthropods.html
  3. EPA, Find the Repellent that is Right for You, search results for DEET, cfpub.epa.gov/oppref/insect_s. https://cfpub.epa.gov/oppref/insect_s/search_results.cfm
  4. EPA, Find the Repellent that is Right for You. https://www.epa.gov/insect-repellents/find-repellent-right-you
  5. EPA notification label, OFF! Insect Repellent II, EPA Reg. No. 4822-380, 15% DEET aerosol, November 13, 2009. https://www3.epa.gov/pesticides/chem_search/ppls/004822-00380-20091113.pdf
  6. CDC, Preventing Mosquito Bites (Wayback Machine capture 2026-09-16). https://www.cdc.gov/mosquitoes/prevention/index.html
  7. McGready R, et al. Safety of the insect repellent N,N-diethyl-M-toluamide (DEET) in pregnancy. Am J Trop Med Hyg. 2001 Oct;65(4):285-9. PMID 11693870. https://pubmed.ncbi.nlm.nih.gov/11693870/
  8. NPIC, DEET General Fact Sheet. https://npic.orst.edu/factsheets/DEETgen.html
  9. EPA, R.E.D. FACTS: DEET, EPA-738-F-95-010, April 1998. https://www3.epa.gov/pesticides/chem_search/reg_actions/reregistration/fs_PC-080301_1-Apr-98.pdf
  10. EPA, Reregistration Eligibility Decision (RED) DEET, EPA738-R-98-010, approved April 13, 1998. https://www3.epa.gov/pesticides/chem_search/reg_actions/reregistration/red_PC-080301_1-Apr-98.pdf
  11. NPIC, DEET Technical Fact Sheet (archived). https://npic.orst.edu/factsheets/archive/DEETtech.html
  12. EPA amended reregistration label, Cutter Insect Repellent #10GE, EPA Reg. No. 121-53, 10% DEET, March 18, 2009. https://www3.epa.gov/pesticides/chem_search/ppls/000121-00053-20090318.pdf
  13. EPA, Using Insect Repellents Safely and Effectively. https://www.epa.gov/insect-repellents/using-insect-repellents-safely-and-effectively
  14. Van Roey K, et al. Field evaluation of picaridin repellents reveals differences in repellent sensitivity between Southeast Asian vectors of malaria and arboviruses. PLoS Negl Trop Dis. 2014 Dec 18;8(12):e3326. PMID 25522134. https://pubmed.ncbi.nlm.nih.gov/25522134/
  15. Carroll JF, Benante JP, Kramer M, Lohmeyer KH, Lawrence K. Formulations of deet, picaridin, and IR3535 applied to skin repel nymphs of the lone star tick (Acari: Ixodidae) for 12 hours. J Med Entomol. 2010 Jul;47(4):699-704. PMID 20695288. https://pubmed.ncbi.nlm.nih.gov/20695288/
  16. NPIC, Picaridin General Fact Sheet. https://npic.orst.edu/factsheets/PicaridinGen.html
  17. EPA, New Pesticide Fact Sheet: Picaridin, May 2005. https://www3.epa.gov/pesticides/chem_search/reg_actions/registration/fs_PC-070705_01-May-05.pdf
  18. EPA stamped master label, Ranger Ready Repellents Tick + Insect Spray, EPA Reg. No. 93221-1, issued January 9, 2018. https://www3.epa.gov/pesticides/chem_search/ppls/093221-00001-20180109.pdf
  19. NPIC, Picaridin Technical Fact Sheet (archived). https://npic.orst.edu/factsheets/archive/Picaridintech.html
  20. EPA stamped label, Associated Registrations Inc. 20% picaridin repellent, EPA Reg. No. 54287-22, July 17, 2019. https://www3.epa.gov/pesticides/chem_search/ppls/054287-00022-20190717.pdf