Permethrin is a broad-spectrum contact insecticide which kills a wide variety of arthropods on contact, including fleas, ticks, scabies, lice, and bees, among many others. This product is sold for a variety of purposes, ranging from flea control in dogs to treatments for wood to deter damage from boring insects. Some caution is advised when using permethrin, as it is fatal to cats and fish, and it has been linked with tumors in laboratory animals.
Historically, permethrin was derived from chrysanthemums, but by the 1970s, it was being produced synthetically. This insecticide works as a neurotoxin, overstimulating the nervous system of insects which come into contact with it. Once of the problems with permethrin is that it is an indiscriminate pesticide, killing all insects which come into contact with it, including beneficial arthropods. Mammals are also at risk of developing health problems if they ingest this insecticide or are exposed to large amounts of it, and some people experience violent allergic reactions when they use it to treat parasitic infestations.
Several companies manufacture permethrin in a wide variety of formats. Sprays can be used to treat a wide area for insects, and they are sometimes used by campers and aid organizations working in developing nations to keep insects out of beds and clothing. Permethrin is also used in the treatment of some wood to prevent insect infestation.
In medical use, topical applications of permethrin are used to prevent fleas in dogs, although pet owners should be aware that these products should never be used on cats. Permethrin creams and lotions are also available to treat lice, scabies, and other parasitic infestations in humans. Typically, only one application is required, as the insecticide will last through several washings.
Before someone uses a permethrin product to treat a parasitic infestation, he should discuss his health with a medical professional. Permethrin can interact poorly with some medications, and it is also not advised for use by pregnant women and nursing mothers. A history of allergies, asthma, and some other conditions may also contraindicate its use.
When using permethrin to treat wood, garments, tents, and so forth, people should be aware that this type is not intended for topical use in humans and other animals, because it is very strong. The material should be allowed to dry completely after an application of spray to avoid coming into direct contact with the permethrin, and wearing gloves during the spraying process can be advisable as well. An application will typically last for two weeks or two washings, whichever comes first.