Permethrin

Permethrin

Chemical structure of permethrin
Clinical data
Trade names	Nix, others
AHFS/Drugs.com	Monograph
Pregnancy category	US: B (No risk in non-human studies)
Routes of administration	topical
ATC code	P03AC04 (WHO) QP53AC04 (WHO)
Identifiers
IUPAC name (±)-3-Phenoxybenzyl 3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropanecarboxylate
CAS Number	52645-53-1
PubChem CID	40326
DrugBank	DB04930
ChemSpider	36845
UNII	509F88P9SZ
KEGG	C14388
ChEBI	CHEBI:34911
ChEMBL	CHEMBL1525
ECHA InfoCard	100.052.771
Chemical and physical data
Formula	C21H20Cl2O3
Molar mass	391.29 g·mol−1
3D model (Jmol)	Interactive image
Density	1.19 g/cm3, solid g/cm3
Melting point	34 °C (93 °F)
Boiling point	200 °C (392 °F)
Solubility in water	5.5 x 10−3ppm mg/mL (20 °C)
SMILES Cl/C(Cl)=C/C3C(C(=O)OCc2cccc(Oc1ccccc1)c2)C3(C)C
InChI InChI=1S/C21H20Cl2O3/c1-21(2)17(12-18(22)23)19(21)20(24)25-13-14-7-6-10-16(11-14)26-15-8-4-3-5-9-15/h3-12,17,19H,13H2,1-2H3 Key:RLLPVAHGXHCWKJ-UHFFFAOYSA-N

Permethrin, sold under the brand name Nix among others, is a medication and insecticide. As a medication it is used to treat scabies and lice. It is applied to the skin as a cream or lotion. As an insecticide it can be sprayed on clothing or mosquito nets such that the insects that touch them die.

Side effects include rash and irritation at the area of use. Use during pregnancy appears to be safe. It is approved for use in people over the age of two months. Permethrin is in pyrethroid family of medications. It works by disrupting the function of the neurons of lice and scabies.

Permethrin was discovered in 1973. It is on the World Health Organization's List of Essential Medicines, the most effective and safe medicines needed in a health system. The wholesale cost in the developing world is about 0.48 to 3.30 USD per tube. In the United States a course of treatment costs 25 to 50 USD and it is available over the counter.

Permethrin is used:

Permethrin is available for topical use as a cream or lotion. It is indicated for the treatment and prevention in exposed individuals of head lice and treatment of scabies.

For treatment of scabies: Adults and children older than 2 months are instructed to apply the cream to the entire body from head to the soles of the feet. Wash off the cream after 8–14 hours. In general, one treatment is curative.

For treatment of head lice: Apply to hair, scalp, and neck after shampooing. Leave in for 10 minutes and rinse. Avoid contact with eyes.

In agriculture, permethrin is mainly used on cotton, wheat, maize, and alfalfa crops. Its use is controversial because, as a broad-spectrum chemical, it kills indiscriminately; as well as the intended pests, it can harm beneficial insects including honey bees, and aquatic life.