How To Treat Your Clothes With Permethrin

True story: I once forgot to pack bug spray for a backpacking trip in the White Mountains of NH. It was my first-ever multi-day backpack, but that excuse didn’t mean a thing to the swarms of black flies that descended upon me over the next several days. It was a pretty rough introduction—I’m originally from NC, where black flies are nonexistent—and quite frankly, I wouldn’t wish it on anyone.

What I do wish is that I’d known about a game-changer of an insect repellent called Permethrin. If I had known about this product, I would’ve been virtually impervious to those suckers, or any other biting insect for that matter. Let’s talk about all things Permethrin, including why you should use it to treat your clothes and gear before your next trip.

What is Permethrin?

Permethrin is a highly effective insecticide that can be used as a first line of defense against biting insects. It is highly toxic to a whole spectrum of insects, including black flies, mosquitoes, and ticks. The best part is that you can treat your clothes with Permethrin before taking your first step into the great outdoors.

Fun fact: Permethrin is a synthetic version of a chemical that is naturally produced by the Chrysanthemum flower. Unlike the natural version, though, Permethrin lasts much longer—once you treat your clothes, it can last for up to six weeks or six washings (whichever comes first).

Can you really treat your clothes with Permethrin?

Yes! You can actually treat your clothes and gear with Permethrin. What article of clothing to focus on depends on what exactly you’re seeking protection from. If your main concern is deer ticks—especially important in areas where Lyme Disease is prevalent—you should concentrate especially hard on your shoes, socks, and the cuffs and waistline of your pants. If mosquitoes are the issue, you should probably go ahead and treat all of your clothing… just saying.

Pro tip: Treat your backpack, too, since it often comes into contact with the ground during rest breaks and whatnot. You don’t want to pick up a hitchhiking tick!

Continue reading the full article on ways to use and treat gear with Permethrin, written by Rachel Shoemaker here.

LAST UPDATED

February 10, 2025

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