Permethrin

Active ingredient: bifenthrin

⚠️ Don't buy duplicates. All brands listed contain the same active ingredient. Buying two different brands is buying the same pesticide twice.
⚖️ Educational use only. Always read and follow the full product label — the label is the law under FIFRA. Full disclaimer → | ⚗️ Mixing Calculator →

⚗️ Clothing Treatment — Best Application

Permethrin-treated clothing kills ticks and mosquitoes on contact — they don't need to bite through the fabric. A tick landing on a treated pant leg is dead within seconds. This is fundamentally different from repellents which just discourage landing. The effect persists through 6+ wash cycles because permethrin binds to fabric fibers.

This single habit — treating your outdoor clothing once per season — is the highest-impact personal tick prevention measure available. More effective than DEET alone. The CDC recommends it for outdoor workers, hikers, and anyone in tick-endemic areas.

Pants, socks, shoes, shirts, hats, and gear (backpacks, tents, sleeping bags). Focus especially on socks and lower pant legs where ticks typically first contact clothing. Treat the exterior surface — not the skin-contact side.

Step 1: Buy clothing spray — Sawyer Permethrin or similar 0.5% spray formulation
Step 2: Treat outdoors — Spray clothing while hanging on a line or laying flat. Wet thoroughly. Keep pets away.
Step 3: Dry completely — Allow 2–4 hours to dry before wearing. Odorless when dry.
Step 4: Lasts 6+ washes — Re-treat after 6 wash cycles or at the start of each season.

🌿 Yard & Perimeter Treatment

For yard tick control, apply permethrin to the lawn-woodland edge (the 9-foot transition zone between maintained grass and wooded areas) in late April and late August. Also treat along fence lines, under decks, and in tall grass areas. Do not apply to flowering plants.

🏷️ Products

Permethrin products — consumer and professional

ProductConcentrationUse
Sawyer Permethrin Spray0.5%Clothing and gear treatment — #1 choice
Martin's Permethrin 10%10% concentrateDilute for yard spray — economical
Bonide Mosquito Beater0.1% RTUReady-to-use yard spray
Permanone (aerosol)0.5%Military/outdoor clothing treatment standard
Gordon's Permethrin 10%10% concentrateLivestock, dogs, yard — versatile concentrate

⚠️ Safety

Permethrin is acutely toxic to cats when wet. Cats lack the liver enzyme (glucuronyl transferase) that metabolizes pyrethroids. Exposure to wet permethrin — even from treated clothing that isn't fully dry — can cause tremors, seizures, and death in cats. Always: treat clothing outdoors, dry completely before bringing inside, and keep cats away from any treated surfaces until fully dry. Dried permethrin on clothing is safe around cats.

Like all pyrethroids, permethrin is highly toxic to fish and aquatic invertebrates. Never apply within 50 feet of water. Do not apply before rain. The aquatic toxicity risk is the primary environmental concern with permethrin yard applications.

Permethrin poses very low toxicity risk to dogs and humans when dry. The EPA classifies it as likely not carcinogenic to humans. The clothing treatment use is considered one of the safest pesticide applications available — the amount absorbed through treated fabric is far below any health threshold.

Example
0.5 oz
per gallon
⚗️ Mixing Calculator
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🐛 Pests This Treats — Learn More

Click any pest to view its full identification guide, biology, and treatment options.

🐛 Ants → 🐛 Mosquito → 🐛 Scales → 🐛 Ticks →

🌿 Environmental & Ecological Impact

🐝 Bees / PollinatorsHIGH
🐟 Fish / Aquatic LifeVERY HIGH
🐦 BirdsLOW
🐕 Mammals / PetsLOW
🦐 Aquatic InvertebratesVERY HIGH
💡 Highly toxic to cats when wet. Extremely toxic to fish and aquatic life.

🔄 Alternatives & Related Products

Same chemical class or different approaches to the same pests.

🔄
Bifenthrin
Same class: Synthetic Pyrethroid
 🔄
Cypermethrin
Same class: Synthetic Pyrethroid
 🔄
Deltamethrin
Same class: Synthetic Pyrethroid
 ↔️
Pyrethrin
Different approach: Botanical Pyrethrin
 ↔️
Boric Acid
Different approach: Inorganic

❓ Frequently Asked Questions

Q: Is permethrin safe for pets?
Safe for dogs once dry, but acutely toxic to cats when wet. Never allow cats to contact wet permethrin.
Q: Can I use permethrin indoors?
Check the specific product label — formulations vary. Baits and dusts often have indoor labeling; concentrates and granulars are typically outdoor.
Q: How long does permethrin last after application?
Residual varies by formulation, surface type, weather, and UV exposure. Indoor applications last longer than outdoor. Check the product label for re-application intervals.
Q: What should I do if exposed?
Remove contaminated clothing, wash skin with soap and water. For eye contact, rinse 15–20 minutes. For ingestion or severe symptoms, call Poison Control (1-800-222-1222). Have the product label available.

📋 Safety Data Sheet (SDS)

📋

Permethrin — Safety Data Sheet

View the official SDS document for this product directly on the CDMS label database.

📄 View SDS on CDMS → 🏛 Search EPA Label Database →
Permethrin Safety Data Sheet page 1
📄 Permethrin — Safety Data Sheet · View the complete SDS document above or download below
📄 CDMS Label & SDS Database 📄 EPA Label Search
📚 Sources: EPA Pesticide Labels · NPIC Pesticide Info
Published: Jan 1, 2025 · Updated: Apr 10, 2026
🔮
Reviewed by Derek GiordanoContent reviewed by a licensed pest management professional and cross-referenced against EPA, university extension, and manufacturer technical data. Last reviewed: April 2026.

Application equipment that improves consistency

Better application equipment improves results more than better product. A one-gallon pump sprayer with adjustable nozzle ($30-50) outperforms hose-end sprayers for residual product application because it delivers consistent dilution. A hand duster ($15-25) is the only effective way to apply dust to wall voids, cracks, and crevices — pre-bottled dust products typically deliver inconsistent coverage. A foam machine adapter is useful for treating wall voids where dust would be inappropriate. Measuring cups and a measuring syringe ensure correct dilution at the label rate. A respirator (organic vapor cartridge) is required for some products and reasonable insurance for others. Equipment investments pay back across many treatments and are usually the missing element when product application produces inconsistent results.

How environmental conditions affect treatment efficacy

Pesticide efficacy is highly sensitive to the conditions at application and immediately after. Temperature affects both vapor pressure (volatility) and residual binding — products applied above ~90°F often volatilize before binding to surfaces, while applications below ~50°F can fail to spread properly. Surface porosity changes residual duration: a residual that lasts eight weeks on a sealed concrete slab might last three weeks on bare wood. Rainfall within four hours of an outdoor application typically washes off most surface deposits, though microencapsulated products are more rain-fast. UV exposure degrades many pyrethroids within days to weeks on sunny surfaces, which is why fence-line applications often fail mid-summer. Indoor humidity affects bait acceptance — dry baits perform worse in high humidity as they absorb moisture and lose palatability. Reading conditions correctly explains many otherwise mysterious treatment failures.

Storing pesticides safely

Pesticide storage at home should follow specific practices for safety and product integrity. Original containers only — label information must remain attached. Locked storage cabinet or location inaccessible to children and pets. Cool, dry environment (not in unheated garages where temperature swings degrade product, and not in direct sun). Don't store with food, beverages, or personal care items. Don't store near ignition sources for flammable products. Keep an inventory and dispose of products that have exceeded shelf life (most pesticides retain efficacy for several years if stored properly, but separated emulsions, crystallized concentrates, or color-changed products should be discarded). Disposal: check with your local hazardous waste program; most municipalities have collection days or permanent drop-off sites for household pesticide disposal.

What's actually in the active ingredient column

Most pesticide products use a small number of active ingredients across many brand names. Pyrethroids (bifenthrin, cypermethrin, deltamethrin, lambda-cyhalothrin, permethrin) are the dominant household residual class — fast-acting, low mammalian toxicity, but increasingly affected by resistance in major pests. Neonicotinoids (imidacloprid, dinotefuran, thiamethoxam) are systemic-leaning and have specific uses for ant baits, termite treatment, and some flea products. Phenylpyrazoles (fipronil) underlie many termite, ant bait, and pet flea products. Insect growth regulators (pyriproxyfen, methoprene, hydroprene, novaluron) interrupt development rather than killing directly and pair well with adulticides. Botanicals (pyrethrum, spinosad) offer rapid knockdown but limited residual. Knowing the active ingredient class lets you rotate products properly and recognize when a 'new product' is really an old active in new packaging.

Choosing the right product formulation for the situation

Active ingredient gets most of the attention, but formulation often determines outcome. The same active ingredient in different formulations performs very differently: microencapsulated formulations last longer on porous surfaces and reduce human re-entry exposure, wettable powders give the longest residual on porous substrates but leave visible residue, suspended concentrates give a balance of residual and appearance, dusts are uniquely effective in wall voids and dry harborage but should never be broadcast indoors, baits are appropriate when pests must transport active to the colony or nest, and aerosols are appropriate for direct contact and quick knockdown but rarely give meaningful residual. Choosing formulation by the substrate (porous vs. nonporous), the access (open spray vs. crack-and-crevice vs. void), and the goal (knockdown vs. residual vs. transferable) routinely improves outcomes more than upgrading active ingredient.

Pesticide rotation and the resistance management problem

Resistance management — using multiple active ingredients in sequence so that no single mode of action selects for resistant individuals — is standard practice in agricultural and commercial pest control but rarely makes it into residential treatment decisions. The underlying concern is real: chronic use of a single pyrethroid product against bed bugs has produced widespread pyrethroid resistance, with some populations now showing resistance factors of 1000x or more. The same pattern is documented in German cockroach resistance to chlorpyrifos and other historical actives, mosquito resistance to organophosphates in heavy-use regions, and house fly resistance across multiple compound classes. For residential treatment, the practical implication is to avoid using the same active ingredient repeatedly across multiple treatment cycles; rotating between products in different chemical families (e.g., pyrethroid → neonicotinoid → insect growth regulator → carbamate, or whatever subset is appropriate to the target pest) reduces selection pressure and preserves efficacy. The product label specifies the active ingredient family, allowing rotation choices to be made on actual chemistry rather than brand name.

How structural moisture issues drive pest problems most homeowners miss

A surprising fraction of pest problems are downstream of moisture issues that go uncorrected because they don't produce obvious damage. Subterranean termites require moist soil contact; correcting drainage and downspouts often reduces termite pressure more than any chemical treatment. Carpenter ants nest in damp or previously-damp wood; the colony moves in only after moisture has softened the substrate. Drain flies, fungus gnats, and springtails are all moisture-driven and resolve when the moisture source resolves. Mold mites and booklice indicate humidity that exceeds about 70%, often in unventilated bathrooms or basements. Even rodent activity correlates with moisture: rodents need accessible water and follow water-supply intrusions to bring themselves into structures. The diagnostic question worth asking on any chronic pest problem: is something wet that shouldn't be? Common offenders are clogged gutters, downspouts that drain near the foundation rather than away from it, condensate lines from HVAC systems and water heaters, slow plumbing leaks under sinks, sweating cold-water pipes in unconditioned spaces, and crawlspaces without adequate vapor barriers. Fixing the underlying moisture issue typically yields permanent improvement that chemical treatment alone cannot match.

Application timing within the day and weather conditions

Pesticide applications produce significantly different results depending on application timing, and matching application to conditions improves outcomes substantially. For outdoor liquid applications, early morning (after dew has evaporated, before pollinators are active) and late evening (after pollinators have stopped foraging, before evening dew) produce best results: temperatures are moderate, wind is typically lower, and non-target exposure is reduced. Mid-day applications during high temperatures cause volatility losses and faster degradation. For interior treatments, timing depends on the pest: cockroach baiting works at any time but should follow rather than precede cleaning; bed bug treatments need to follow vacuuming and clutter reduction; ant baits work best when active trails are present, which often means specific times of day for specific species. Rain within 4 hours of outdoor liquid application washes off most surface residue except specifically rainfast formulations; checking the next 24-hour forecast before any outdoor treatment is the basic discipline that prevents this loss. Temperatures above 90°F or below 50°F outside the product label's recommended range produce reduced efficacy.

Reduced-risk pesticide selection: a category worth knowing

The EPA's reduced-risk pesticide program identifies active ingredients and formulations that meet specific criteria for lower toxicity to non-target organisms, reduced potential for groundwater contamination, lower likelihood of resistance development, or better compatibility with integrated pest management. Products in this category aren't free of toxicity — they're pesticides, and all pesticides have some toxic profile — but they represent the lower end of the risk distribution within their pest categories. For homeowners who want to use pesticides but are concerned about minimizing exposure and environmental impact, looking for products with reduced-risk actives is a defensible filter. Examples include some of the diamide insecticides, spinosyns, and certain microbial products. The catch is that retail availability lags behind the professional market for many reduced-risk products, and consumer pesticide aisles still skew heavily toward older pyrethroid and carbamate formulations. For homeowners willing to source products from agricultural supply channels or work with a pest control company that uses these products, the option exists; for those buying off the shelf at typical retail, the choices are narrower.

The role of inspection in long-term cost reduction

An inspection is the cheapest tool in pest management, and homeowners systematically underspend on it. The economics are unambiguous: an annual or semiannual inspection costs a small fraction of what any moderate treatment costs, and it catches problems while they're still cheap to address. Termite damage detected in its first season requires perimeter treatment; the same damage discovered three years later may require structural repairs running into five figures. Rodent activity detected through droppings before nesting establishes requires sealing and a few traps; the same activity discovered after a multi-generation infestation has set up in wall voids requires removal, exclusion, sanitation, and sometimes drywall work. The pattern repeats across nearly every pest category. Even households that don't engage a regular pest service should treat the annual inspection as a baseline expense — equivalent to the way they probably treat HVAC tune-ups, gutter cleaning, or smoke detector battery changes. The marginal cost of one trained set of eyes on the property each year is one of the most defensible expenses in home maintenance.

Pesticide drift and the neighbor dimension

Pesticide drift — the off-target movement of applied product through air, water, or runoff — is an under-discussed dimension of residential pesticide use, but it's an increasingly common source of conflict between neighbors and a real factor in the cumulative environmental load of pesticide use. Foliar sprays applied in even light wind drift further than most homeowners expect, particularly with finer droplet sizes. Granular products applied near property lines wash into adjacent properties in significant rainfall. Mosquito fogging can move across multiple properties depending on conditions. The implications are partly legal — drift onto neighboring property without consent has been the basis of successful nuisance claims in some jurisdictions — and partly ethical. Applying products only in low-wind conditions, choosing coarser droplet sizes when possible, using granulars rather than sprays near property lines, and timing applications to avoid imminent rainfall all reduce drift. For homeowners concerned about pesticide exposure from neighbors' applications, the productive conversation is usually about timing and product choice rather than about pesticide use in general, and approaching it that way tends to produce cooperation rather than escalation.