Permethrin is a synthetic version of the Chrysanthemum flower’s natural insect repellent pyrethrin. The naturally occurring version breaks down rather quickly in sunlight but Sawyer’s pharmaceutical grade, synthetic Permethrin can last 6 weeks or 6 washings on clothing and other fabrics, making it a fantastic odorless barrier of protection from mosquitoes and ticks.

Yes once the treatment has fully dried, Sawyer Permethrin treated clothing and gear is completely safe to use wear around cats. Concentrates and agricultural grade formulas pose a much higher threat than our pharmaceutical grade formula.

It is during the application process which cats need to be separated. Do not expose cats to wet permethrin as it affects their central nervous system. This is not true with dogs, horses, or cows. Cats can be around permethrin treated fabrics once the application has dried.

No, the amount of Sawyer Permethrin Fabric Insect Repellent that can come out via physical contact or water contact is indeterminately small once the treatment has fully dried and bonded with the fabric fibers with our pharmaceutical grade formula. This is not the case for other brand concentrates or agricultural grade formulas.


With the Sawyer formula, think of it like the dye in a t-shirt. It will slowly degrade via UV exposure or the heavy agitation of a washing machine but not be immediately noticeable. You can extend the performance of Sawyer Permethrin treatment fabrics by hand washing them or limiting UV exposure between uses.

No. Permethrin will not damage clothes or equipment. Unlike DEET, which may harm some fabrics and materials, Permethrin is compatible for use even on fragile fabrics such as silk, plus all synthetics and waterproof membrane fabrics. Permethrin will not affect plastics or finishes. IF IN DOUBT, try a sample on an obscure surface area, especially on delicates and check it after 24 hours of exposure.Sawyer® Permethrin Insect Repellent is odorless, non-greasy and non-staining after it dries. Permethrin can be harmful to aquatic creatures such as fish, so do not spray Permethrin around fish aquariums.

It is recommended that treating clothing with the permethrin aerosol be performed outdoors. If the treatment is accidentally carried out indoors, no adverse health effects are expected based upon calculations of inhaled dose. However, individuals with breathing problems, such as asthma, may be at greater risk. The odor arising from treating fabric with permethrin is mostly from the aerosol propellants rather than from the insect repellent itself.

A strong bond is formed between permethrin and most fabrics. In fact, some insect repellency was observed in military uniforms following 50 launderings. However, the uniforms were treated using an absorption method instead of the aerosol can. In studies performed by the U.S. Army, about 20 to 30 percent of the permethrin treatment was removed after the first laundering. Thereafter, about 3 to 5 percent was lost to each cycle through ten launderings.

Studies in animals have demonstrated that no skin irritation or sensitization is expected following direct application. In a controlled human study, permethrin did not cause significant skin irritation or sensitization when tested in 200 subjects. No significant skin effects are expected from wearing permethrin-treated clothing.

The pump spray version of our Permethrin Insect Repellent Treatment will not harm flame retardant garments.