IR3535 vs. picaridin: which mosquito repellent should you buy?

Start with 20% picaridin for a long outing

For a full day outside, start your search with a 20% picaridin spray or lotion. Match its mosquito protection time to your plans. It is a useful first choice when you carry plastic gear and want a repellent without DEET.

Choose IR3535 when you prefer the feel of a specific labeled formula and its protection time fits your day. There is no need to replace a repellent that already suits you just because another bottle has a more familiar ingredient.

Both ingredients appear in EPA-registered skin repellents recommended by CDC. Neither turns your yard into a mosquito-free zone. This choice is about the bottle you will carry, apply, and reapply as directed.

Sources: CDC: preventing mosquito bites · University of Illinois: repellent materials and use

Affiliate disclosure: We may earn a commission from qualifying purchases through links on this site. This does not change what you pay.

What changes between the two?

Look past the words “DEET-free.” Compare the full label, format, and outing. A low-strength lotion and a stronger spray are not a fair test of two ingredients.

Buying question	Picaridin	IR3535
What name should I look for?	Picaridin; also called icaridin	IR3535; often a longer chemical name on the label
Which strength should I compare?	20% is a useful starting point for long outings	Check the percentage and the exact mosquito claim together
Does the ingredient set the hours?	No; spray and lotion may differ	No; different formulas may differ
What about plastic gear?	Usually the easier fit; check the whole formula	May damage some plastics and clothing
Is sunscreen built in?	Check the bottle	Some products combine the two; others do not
What is the main buying trap?	Assuming every picaridin bottle has the same strength	Assuming all IR3535 formulas match an old low-strength product

For either type, find the EPA registration number on a US product. Read the mosquito claim, age directions, and use limits before comparing package size. EPA registration concerns the product’s labeled use; it is not a premium-quality award.

Sources: EPA: choose a repellent by pest and protection time · EPA: how skin-applied repellents are regulated · University of Illinois: repellent materials and use

Compare hours on the exact bottle

Buy enough labeled protection for the outing, with a plan for reapplication. More active ingredient may extend protection, but percentages do not let you convert one ingredient into another. “Up to” is not a timer that guarantees no bites.

These manufacturer examples show why the finished formula matters:

Picaridin example

Sawyer lists up to 12 hours against mosquitoes and ticks for its 20% spray, and up to 14 hours for its 20% lotion. The same active percentage has different claims by format.

IR3535 example

Zevo lists up to 8 hours for its On-Body pump spray. Do not apply that number to every IR3535 bottle, or to Zevo’s household insect-killer sprays.

These are label-reading examples, not a head-to-head test. A manufacturer’s longest stated time does not prove its product will beat another formula on your hike.

Sources: Sawyer: 20% picaridin spray and lotion specifications · Zevo: On-Body pump spray specifications

An EPA label for Bug Repell IR3535 20% Spray allows reapplication around eight hours, or sooner if needed, with no more than three applications daily. That is one formula’s rule, not a rule for all IR3535 products. Your bottle’s directions control.

Sources: EPA: Bug Repell IR3535 20% Spray label, June 2025

Read our spray, lotion, and wipes comparison if the application style is the harder choice.

Who should buy each type—and who should skip it?

Choose picaridin for gear-heavy days

It is a practical first comparison for fishing, hiking, or work with plastic glasses and tools. Pick a format you can spread evenly. Skip a bottle whose mosquito claim is too short for the job.

Choose IR3535 for a formula you like using

A suitable registered formula is a valid choice for walks, gardening, and other outings. Skip a sunscreen combo if separate reapplication schedules would be simpler.

Choose lotion for controlled placement

It is easier to place without spraying nearby objects. The tradeoff is more rubbing in. A thick layer is not a substitute for following the label.

Choose spray for convenient coverage

A pump can be easy to carry and apply. The tradeoff is drift and overspray. Use it away from food and avoid breathing the mist.

Skip both as a room treatment. A skin repellent has no square-foot coverage claim for a bedroom or patio. For a two-person balcony, both people need protection. Buying a bigger skin-repellent bottle does not create a bigger protected zone.

Use the product finder to compare personal protection with tools for your setting. The picaridin product page explains the spray format. For the main ingredient alternative, see picaridin vs. DEET and the DEET format page.

Sources: EPA: safe use and application · University of Illinois: repellent materials and use

Plan the cost per person, not per yard

These are US-dollar planning ranges, not live prices or quotes for a named product. Pack size, seller, shipping, and formula change the total.

Your plan	Starting allowance	What to prioritize
One person trying a formula	$10–$25	One small labeled bottle; avoid a bulk pack before you know the feel
Two adults on regular outings	$20–$50	A bottle each or a home bottle plus a carry size
Family travel supply	$40–$90	Enough separate containers for the group and access to replacements
Separate sun protection	$10–$25 extra	A sunscreen that suits the people and activity

A $50 two-person starting budget: allow $15 for each repellent bottle and $20 for separate sunscreen. That is a spending plan, not a promise that two bottles will last a certain number of days.

For matching formulas, compare delivered cost per fluid ounce. An example $15 bottle with 3 fluid ounces costs $5 per ounce. A $24 bottle with 8 fluid ounces costs $3 per ounce. The larger bottle saves money only if you can use and carry it.

Do not compare an aerosol’s net-weight ounces with a lotion’s fluid ounces as if they were the same measure. And do not stretch a bottle by using less than its directions require.

There is no reliable “applications per family” figure without knowing the product, exposed skin, and labeled amount. Note how much you use on ordinary outings, then plan your next purchase. Our bulk-buying and storage guide helps with the next step.

Skin comfort, children, and gear

Neither ingredient wins for every person’s skin. A fragrance-free claim does not tell you whether the formula contains alcohol or other ingredients you avoid. Check the full label and start with a small package. Do not try it on broken or irritated skin.

IR3535 can irritate eyes. Picaridin can also cause skin or eye irritation. If a reaction occurs, stop using the product, wash it off, and follow its first-aid directions. Get medical advice for a concerning or persistent reaction.

Sources: NPIC: repellent ingredients, exposure, and skin reactions

CDC includes both ingredients among repellent options for children and considers registered repellents safe during pregnancy and breastfeeding when used as directed. Follow the exact label. Adults should apply children’s repellent, keeping it off their hands. Use suitable clothing and netting for babies too.

Sources: CDC: preventing mosquito bites

Keep IR3535 away from plastic gear unless the label and gear maker allow contact. With either type, apply away from glasses, phone screens, and finished surfaces, and wash residue from your hands before handling food. Human repellent is not a treatment for a dog or cat.

Sources: University of Illinois: repellent materials and use · EPA: safe use and application

See the sensitive-skin guide or family repellent guide for a closer look.

Sunscreen and travel change the choice

For days in the sun, buy separate sunscreen and repellent. CDC advises this because sunscreen may need more frequent or heavier use. Apply sunscreen first, then repellent, and follow each label. Do not add more repellent just because it is time for sunscreen.

IR3535 does not always come with SPF. Check the exact formula instead of ruling out the whole ingredient. A sunscreen-repellent combo can also be an awkward purchase for evening use when you only need the repellent.

Sources: CDC Yellow Book: travel repellents and sunscreen

For travel where malaria is a risk, arrange advice before the trip. UKHSA’s 2026 guidance recommends a 20% formula when choosing picaridin. It also calls IR3535 effective, while noting that more frequent use may be needed than with DEET. Neither bottle replaces any malaria medicine recommended for your destination.

Choose a labeled product you can use often enough, plus clothing and suitable sleeping protection. Do not turn an older study’s average time into a guarantee for a different bottle. See our tropical travel kit guide and sunscreen comparison.

Sources: UKHSA: 2026 travel bite-prevention guidance · CDC Yellow Book: travel repellents and sunscreen

Why a good repellent can still fail

A bottle with a long stated time can still disappoint when the routine does not fit the day. Before paying for a different ingredient, check these common gaps.

Missed skin: exposed ankles or areas around cuffs may have been left untreated.
Sweat, water, and rubbing: activity can shorten protection. Read the rules for reapplication after swimming or heavy sweating.
The wrong claim: tick protection time is not automatically mosquito protection time. Check both when you need both.
A product mix-up: regular bath oil is not the same as labeled Bug Guard repellent. Household bug killer is not skin repellent.
A bottle left at home: an extra-large package is poor value if it is too awkward to bring when you need it.

If bites start, follow the label’s reapplication rules. If you have reached its limit, cover exposed skin or move to a screened space. Do not layer different repellents to invent a longer protection time.

Sources: EPA: choose a repellent by pest and protection time · EPA: safe use and application · Zevo: On-Body pump spray specifications

For repeat trouble at home, check screens and empty water-holding items as well. A repellent choice will not fix a breeding site. Dunks vs. bits explains when water treatment belongs in the plan.

Sources: CDC: preventing mosquito bites

Check these six things before ordering

Exact formula: active ingredient, percentage, and mosquito claim.
Use limits: age directions, reapplication rules, and daily maximum.
Format: spray or lotion you will actually carry and use.
Fit: skin preferences, gear materials, and separate sun protection.
Package: correct size, count, readable label, and sealed container.
Delivered cost: compare like units and avoid buying a season’s supply of an unfamiliar formula.

For most long outings, compare a suitable 20% picaridin formula first. Keep IR3535 on the list when its exact label and feel suit you. If you already like DEET, there is no need to change simply to get a DEET-free claim.

Buyer questions

Is IR3535 the same as picaridin?

No. They are different repellent ingredients. Picaridin is also called icaridin. IR3535 may be listed as ethyl butylacetylaminopropionate. Check the active ingredient and percentage on the bottle.

Which should I choose for a long day outside?

Start by comparing 20% picaridin formulas with a mosquito protection time that fits your outing. A labeled IR3535 formula can also fit. Choose by the finished product and its use limits, not by the ingredient name alone.

Does 20% IR3535 last as long as 20% picaridin?

The same percentage does not promise the same hours. Spray, lotion, other ingredients, and test conditions can change the result. Compare the mosquito claim on each exact label.

Is IR3535 a natural repellent?

It is a man-made ingredient based on a substance found in nature. That does not make a finished bottle chemical-free or suitable for every person. Look for a registered skin repellent and follow its directions.

Is regular Skin So Soft bath oil the same as Bug Guard?

No. A bath oil and a labeled insect repellent are different products. Do not use a familiar brand name as proof of mosquito protection. Read the active-ingredient panel and mosquito claim.

Does every IR3535 repellent contain sunscreen?

No. IR3535 comes in products without sunscreen too. Check the exact bottle. For sun exposure, separate sunscreen and repellent let you follow each product’s own reapplication directions.

Can I use either ingredient on children?

CDC includes picaridin and IR3535 among options for children. Follow the exact product label and have an adult apply it. Do not put repellent on a child’s hands. Clothing and suitable netting also help protect babies.

Can I use them while pregnant or breastfeeding?

CDC considers EPA-registered repellents safe when used as directed, including during pregnancy and breastfeeding. Choose by the product label rather than a natural or DEET-free claim.

Which is best for sensitive skin?

Neither ingredient guarantees comfort. Fragrance, alcohol, and the rest of the formula matter too. Start with a small package of a formula you can use as directed. Avoid broken or irritated skin; stop use and wash it off if a reaction occurs.

Can IR3535 damage sunglasses or fishing gear?

It can damage some plastics and clothing. Check both the repellent and gear instructions, and keep spray off lenses and finished surfaces. Picaridin is often the easier choice around plastic gear, but still follow the whole product’s directions.

Can I put on sunscreen after applying repellent?

Plan to apply sunscreen first, then repellent, following both labels. Reapply each when its own directions require. Do not add repellent automatically each time you add sunscreen.

What if I swim or sweat a lot?

Water, sweat, and rubbing can shorten protection. Check the label before reapplying and stay within its daily limits. If more repellent is not allowed, cover up or move to a screened space.

Can I mix IR3535 and picaridin for stronger protection?

Do not blend bottles or make your own mixture. Choose one labeled formula that fits the outing. Two ingredient names do not establish a tested protection time for a homemade mix.

Can I use IR3535 for a trip where malaria is a risk?

CDC lists IR3535 as a repellent option. Current UK guidance also calls it effective but notes more frequent use may be needed than with DEET. Plan the full trip with a travel clinician; repellent does not replace any recommended malaria medicine.

Will either repellent protect everyone on my patio?

Skin repellent protects the person wearing it on the areas treated as directed. It does not provide a yard or room coverage rating. Each person needs their own protection plan.

Can I use a human repellent on my dog or cat?

Only use a product on an animal if its label explicitly allows that use. A human-skin repellent is not a pet treatment. Ask your veterinarian about protection for your pet.

Sources and product labels

For application, reapplication, and storage, follow the directions on the bottle you buy.