What's actually
in bug spray?

Q: Does a higher percentage mean a stronger repellent?

Longer, not stronger. CDC's Yellow Book says higher concentrations of active ingredient generally provide a longer duration of protection, regardless of the active. NPIC says higher-concentration repellents may protect for longer but are not better at keeping insects away, and that products under 10 percent may only protect for one to two hours. For DEET, CDC's Yellow Book says studies suggest efficacy tends to peak near 50 percent, with no marked increase in protection time against mosquitoes above that.

Q: Are the "natural" oil repellents regulated at all?

Some sell without registration, which is a different thing from being tested. EPA's page names citronella, cedar, geranium, peppermint and soybean oil as examples of ingredients in unregistered repellents. EPA says it evaluated those ingredients for safety in the 1990s, found minimal risk at the percentages on the market, and exempted products made from them, and that those products have not been evaluated for effectiveness. EPA has also said it is considering a future rule to remove personal mosquito and tick repellents from that exemption, which would require them to register before sale.

Q: Can a repellent label say it stops Lyme disease or West Nile virus?

Not in those words. EPA's Label Review Manual lists statements that imply a product can prevent or control disease, such as an insecticide claiming control of Lyme disease, among its examples of unacceptable claims. What EPA does review is efficacy data when a product claims to control a pest that poses a threat to human health. That is why the rows on this page name pests, and quote CDC about what those pests carry, instead of naming diseases a repellent stops.

Q: If EPA's tool says 12 hours, will my bottle last 12 hours?

Treat it as the label's claim under test conditions, not a promise for your afternoon. EPA says the protection times in its tool come from technical information the company supplied, gathered under scientific testing guidelines, and that results vary with testing conditions. Some products carry an asterisk, meaning the company chose not to attach a specific time, and an X means the product is not registered for ticks. EPA also notes that the tool's database was last updated in June 2019.

Type the spray in your hand, or the ingredient on its label.

Ten active ingredients do the work in every registered repellent. Each has a page here, built from what EPA, CDC and NPIC have put in writing: 69 sources, every line opens to its quote. Updated 2026-09-22.

The ten.

In the order EPA lists them. Hours are EPA's own, across every product listed with that active.

DEETSynthetic2 to 12 h mosquitoes, 2 to 10 h ticks PicaridinSynthetic, modeled on a pepper compound3 to 14 h mosquitoes, 5 to 14 h ticks IR3535Synthetic, modeled on an amino acid2 to 10 h mosquitoes, 2 to 12 h ticks Oil of lemon eucalyptusPlant-derived, refined6 h mosquitoes, 6 h ticks PMDSynthesized copy of OLE's active2 h mosquitoes, 2 h ticks 2-UndecanonePlant-derived or synthetic5 h mosquitoes, 2 h ticks Catnip oilPlant-derived7 h mosquitoes CitronellaPlant-derived1 to 3 h mosquitoes, 1 h ticks Other plant oilsPlant-derived, unregisteredNot in EPA’s tool PermethrinSynthetic pyrethroidNot in EPA’s tool

Came with a situation?

TicksWhich actives EPA lists for ticks, and what goes on clothing.DEET-freeThe nine other EPA actives, and the products listed under them.My kidAge rules from CDC and EPA, active by active.Pregnant or breastfeedingWhat CDC and the trials say.My dog or catLabels, NPIC, and the permethrin warning for cats.Picaridin or DEETThe two most asked about, side by side.The natural stuffWhat EPA registers, what it exempts, what it says about testing.

How this was builtWhere we sit, the method, common questions, and every source.

Where we sit. Longsleeve is a 20% picaridin lotion, EPA Reg. No. 101457-1, sold by Hour 72, Inc. It is not in the EPA repellent search tool listing that the record above is built from: EPA says that database was last updated in June 2019, and this product was registered in December 2025, so the 55 picaridin products counted in the row belong to other companies. The DEET row comes first on this page, the "Pick two" view opens on DEET, and the shortcut pairs split evenly. If you want our ingredient list, it is on the ingredients page; the label is on the product page.

How to read these pages.

We sell a product built on one of these actives. That is exactly why this page has no opinion in it. A company that sells picaridin does not get to tell you picaridin is the one to buy; the agencies decide what can be said, and we print what they said.

The rows are the active ingredients EPA registers for use on skin, plus permethrin, which CDC says should never be applied to skin and only to clothing, nets and other fabrics. The plant oils that sell as repellent without registration get one row of their own, because the rule that lets them sell without registration is a fact too.

Protection times are not ours. They are the range EPA's own repellent search tool listed across every product with that active, mosquitoes and ticks separately, on the date we pulled it. Each product carries its own approved time, or none at all; the active's row shows the spread. Strengths are the concentrations EPA lists for the same products. EPA's page says it endorses no product, and says the information in that database was last updated in June 2019.

Every other cell reports what a source said, and prints the sentence it came from. Open the source line under any answer and the exact words appear, with a link to the page or PDF they came from. Where an agency has not said anything, the cell says so. We did not fill gaps with marketing copy, a blog, or our own view. Where a cell rests on an EPA-accepted label rather than an agency statement, it says so.

Three things you will not find here. A "safest" column: no agency we read ranks the registered actives against each other on safety, so there is nothing to put in it. A price column: prices move by retailer and week, so there is nothing stable to cite. A disease column: EPA's Label Review Manual lists claims to prevent or control disease among unacceptable claims, and what EPA reviews is efficacy against the pest, so a repellent is registered to repel a pest. Where CDC names what a pest carries, we quote CDC about the pest.

Source: CDC, CDC Yellow Book, EPA, U.S. EPA

Protection Times - These protection times have been approved for product labels. These times are based on the technical information provided by the company on the effectiveness of the product against mosquitoes and/or ticks.
EPA, Find the Repellent that is Right for You, search results for picaridin, cfpub.epa.gov/oppref/insect_s

Permethrin should never be applied to the skin but only to clothing, mosquito nets, or other fabrics as directed on the product label.
CDC Yellow Book, Mosquitoes, Ticks, and Other Arthropods (Wayback Machine capture 2026-09-19)

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

An asterisk ( * ) indicates that EPA has technical information on the effectiveness of the product against mosquitoes and/or ticks and the company chose not to have a specific time associated with their product. * An " X " indicates that the repellent product has not been registered for protection from ticks.
U.S. EPA, Insect Repellents: Use and Effectiveness search results

III. Some examples of unacceptable claims ► Statements that imply or suggest that the product can or will prevent or control disease or offer health protection, such as an insecticide that claims control of Lyme disease.
U.S. EPA, Label Review Manual, Chapter 12: Labeling Claims, November 2013

EPA routinely reviews efficacy data (also referred to as product performance data) when a pesticide product bears a claim to control pest organisms that pose a threat to human health.
U.S. EPA, Label Review Manual, Chapter 12: Labeling Claims, November 2013

Some insect repellent products for sale in the United States do not currently require EPA registration. In the 1990s, EPA evaluated the active ingredients in these unregistered products for safety . We determined that the active ingredients posed minimal risk to human health in the percentages found in products on the market.
U.S. EPA, Regulation of Skin-Applied Repellents

Almost everyone has been bitten by a mosquito. Mosquitoes can spread pathogens (germs) through bites. A person who gets bitten by a mosquito and gets sick has a mosquito-borne disease like West Nile virus, dengue, or malaria.
CDC, About Mosquitoes (Wayback Machine capture of cdc.gov/mosquitoes/about/index.html)

In the United States, some ticks carry pathogens that can cause human disease, including: * Alpha-gal syndrome * Anaplasmosis * Babesiosis * Bourbon virus * Colorado tick fever * Ehrlichiosis * Hard tick relapsing fever * Heartland virus * Lyme disease * Powassan virus * Rickettsia parkeri rickettsiosis * Rocky Mountain spotted fever * Soft tick relapsing fever * STARI * Tularemia
CDC, About Ticks and Tickborne Disease (Wayback Machine capture of cdc.gov/ticks/about/index.html)

Common questions.

What does an EPA registration number on a repellent actually mean?

EPA says it means the company gave EPA technical information on the product's safety and its effectiveness against mosquitoes and/or ticks, and EPA registered it. EPA's own page puts it plainly: look for the EPA Reg. No. on the label, and CDC recommends products registered by EPA. A repellent with no registration number has not been evaluated by EPA, and EPA says it cannot advise consumers on how well those products work.

Source: U.S. EPA

Look for an EPA registration number (EPA Reg. No.) on the insect repellent product label. This registration number means the company provided EPA with technical information on the effectiveness of the product. The Centers for Disease Control and Prevention (CDC) recommends the use of products registered by EPA.
U.S. EPA, Using Insect Repellents Safely and Effectively

The registration number means the company provided EPA with technical information on the safety of the product and its effectiveness against mosquitoes and/or ticks. 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.
U.S. EPA, Find the Repellent that is Right for You

Repellents that do not bear an EPA registration number have not been evaluated by EPA, and EPA cannot advise consumers about the effectiveness of these products.
U.S. EPA, Regulation of Skin-Applied Repellents

Does CDC recommend one active ingredient over the others?

No. CDC's tick-prevention page lists six actives by name, DEET, picaridin, IR3535, oil of lemon eucalyptus, PMD and 2-undecanone, and tells you to look for the EPA registration number on the label. Its Yellow Book says EPA-registered repellents have been proven effective in reducing biting by mosquitoes, sand flies, ticks and mites. Neither page ranks the six.

Source: CDC, CDC Yellow Book 2024

Use Environmental Protection Agency (EPA)-registered insect repellents containing DEET, picaridin, IR3535, Oil of Lemon Eucalyptus (OLE), para-menthane-diol (PMD), or 2-undecanone. Look for an EPA registration number (EPA Reg. No.) on the insect repellent product label. This registration number means the company provided EPA with technical information on the effectiveness of the product.
CDC, Preventing Tick Bites (Wayback Machine capture of cdc.gov/ticks/prevention/index.html)

Insect repellents registered by the Environmental Protection Agency (EPA) have been proven effective in reducing biting by insects such as mosquitoes and sand flies, as well as other arthropods, such as ticks and mites.
CDC Yellow Book 2024, Mosquitoes, Ticks, and Other Arthropods (Wayback Machine capture)

Which actives can go on children, and from what age?

CDC's Yellow Book says repellents containing DEET, picaridin, IR3535 and 2-undecanone can be used on children without age restriction. CDC says not to use oil of lemon eucalyptus or PMD on children under 3, with one exception the Yellow Book spells out: certain products with OLE as the sole active at 30 percent or less can be used under 3, and parents should read the label first. NPIC adds that if no age limit is on the label, EPA has not put an age restriction on the product, and that the American Academy of Pediatrics does not recommend repellents for children younger than two months.

Source: CDC, CDC Yellow Book 2024, NPIC

Insect repellents containing DEET, picaridin, IR3535, and 2-undecanone can be used on children without age restriction (see EPA webpage on Using Insect Repellents Safely and Effectively with Children ).
CDC Yellow Book 2024, Mosquitoes, Ticks, and Other Arthropods (Wayback Machine capture)

Do not use products containing OLE or PMD on children under 3 years old.
CDC, Prevent Mosquito Bites (Wayback Machine capture of cdc.gov/mosquitoes/prevention/index.html)

Certain insect repellent products containing OLE as their sole active ingredient at concentrations of ≤30% can be used on children <3 years of age; parents should always read the product label before use.
CDC Yellow Book 2024, Mosquitoes, Ticks, and Other Arthropods (Wayback Machine capture)

Check the product label to see if there is a minimum age for use. If no age limit is on the label, the EPA has not put age restrictions on the product.
NPIC, Insect Repellents General Fact Sheet

The American Academy of Pediatrics (AAP) does not recommend insect repellents for children younger than two months. 25
NPIC, Insect Repellents General Fact Sheet

Does a higher percentage mean a stronger repellent?

Longer, not stronger. CDC's Yellow Book says higher concentrations of active ingredient generally provide a longer duration of protection, regardless of the active. NPIC says higher-concentration repellents may protect for longer but are not better at keeping insects away, and that products under 10 percent may only protect for one to two hours. For DEET, CDC's Yellow Book says studies suggest efficacy tends to peak near 50 percent, with no marked increase in protection time against mosquitoes above that.

Source: CDC Yellow Book, CDC Yellow Book 2024, NPIC

In general, higher concentrations of active ingredients provide longer duration of protection, regardless of the active ingredient.
CDC Yellow Book 2024, Mosquitoes, Ticks, and Other Arthropods (Wayback Machine capture)

Higher concentration repellents may protect people for longer. However, they are not better at keeping insects away. 5,6,7 Repellents with less than 10% of an active ingredient may only offer protection for short periods of time (1-2 hours). 5
NPIC, Insect Repellents General Fact Sheet

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)

Are the "natural" oil repellents regulated at all?

Some sell without registration, which is a different thing from being tested. EPA's page names citronella, cedar, geranium, peppermint and soybean oil as examples of ingredients in unregistered repellents. EPA says it evaluated those ingredients for safety in the 1990s, found minimal risk at the percentages on the market, and exempted products made from them, and that those products have not been evaluated for effectiveness. EPA has also said it is considering a future rule to remove personal mosquito and tick repellents from that exemption, which would require them to register before sale.

Source: U.S. EPA, US EPA

Some insect repellent products for sale in the United States do not currently require EPA registration. In the 1990s, EPA evaluated the active ingredients in these unregistered products for safety . We determined that the active ingredients posed minimal risk to human health in the percentages found in products on the market.
U.S. EPA, Regulation of Skin-Applied Repellents

Examples of ingredients used in unregistered repellents are: Citronella oil. Cedar oil. Geranium oil. Peppermint and peppermint oil. Soybean oil.
US EPA, Regulation of Skin-Applied Repellents, last updated June 25, 2026

In the 1990s, EPA evaluated the active ingredients in these unregistered products for safety . We determined that the active ingredients posed minimal risk to human health in the percentages found in products on the market. Based on this minimal risk determination, we decided that products made from these ingredients should be exempt from registration. Note that products made from these ingredients have not been evaluated for effectiveness .
US EPA, Regulation of Skin-Applied Repellents, last updated June 25, 2026

Repellents that do not bear an EPA registration number have not been evaluated by EPA, and EPA cannot advise consumers about the effectiveness of these products.
US EPA, Regulation of Skin-Applied Repellents, last updated June 25, 2026

To that end, we have explored rulemaking regarding personal insect repellents and in a future rulemaking are considering a proposal to remove personal mosquito and tick repellents from the minimum risk pesticides exemption currently in 40 CFR 152.25(f). This means that once removed from the exemption, personal mosquito and tick repellents would need to be registered as a pesticide product with EPA before sale or distribution in the United States.
US EPA, Personal Insect Repellents and Minimum Risk Pesticides

Can a repellent label say it stops Lyme disease or West Nile virus?