(redirected from Pyrethrins)
Also found in: Medical, Encyclopedia.
Related to Pyrethrins: permethrin, pyrethroids, Piperonyl butoxide


 (pī-rē′thrĭn, -rĕth′rĭn)
Either of two viscous liquid esters, C21H28O3 or C22H28O5, that are extracted from pyrethrum flowers and used as insecticides.

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. (Elements & Compounds) Also called: pyrethrin I an oily water-insoluble compound used as an insecticide. Formula: C21H28O3
2. (Elements & Compounds) Also called: pyrethrin II a compound of similar chemical structure and action, also found in pyrethrum. Formula: C22H28O5
[C19: from pyrethrum + -in]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(paɪˈri θrɪn, -ˈrɛθ rɪn)

either of two chemicals, C21H28O3 or C22H28O5, extracted from pyrethrum flowers: used as an insecticide.
[1830–40; pyrethr (um) + -in1]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


n piretrina
English-Spanish/Spanish-English Medical Dictionary Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.
Mentioned in ?
References in periodicals archive ?
According to the Sun: "The 2016 study of 48 US states found that head lice were able to grow gene mutations, which helped them resist insecticides, also known as pyrethrins, pyrethroids and permathrins."
Based on data from the dermatological archives at the National Institutes of Health, the Vamousse brand says leading products utilizing the common chemical pesticides permethrin and pyrethrins are becoming far less efficacious as strains of lice have built up resistance to them.
It is an insecticide belonging to the pyrethroid family, man-made versions of pyrethrins -- natural insecticides from chrysanthemum flowers.
Using permethrins (also Pyrethrins) can lead to generalized tremors, seizures, and death.
Manzoor and Sattar (2013) state that R dominica is generally tolerant to many organophosphates (including DDVP), however, a field warehouse experiment by Aulicky and Stejskal (2013) showed that aerosol mixtures of DDVP + natural pyrethrins provided instant 100% mortality in most of the geographical strains of R.
It contains natural pyrethrins to kill fleas and ticks on contact and will keep on killing for up to 14 days; EPA registered.
Five insecticides were used in the experiment: (1) Confidor (17.8% imidacloprid, Bayer East Africa, Nairobi, Kenya); (2) Fastac (10% alpha-cypermethrin, BASF Corporation, Nairobi sub-office; Nairobi, Kenya); (3) Pyrethrum 5EW (5% pyrethrins, Agropy Ltd, Kigali, Rwanda; (4) Pyrethrum EWC (2.19% pyrethrins and 10% sesame, Agropy Ltd, Kigali, Rwanda); and (5) Agroblaster (8% pyrethrins, SOPYRWA, Musanze, Rwanda).
Pyrethroids are man-made versions of pyrethrins, the natural insecticides from pyrethrum.
A shampoo that contains pyrethrins, such as Bayer Advantage Flea & Tick Treatment Shampoo, Biogroom Flea & Tick Shampoo, or Ovitrol Plus Flea & Tick Shampoo, will kill adult fleas.
A review of the relationship between pyrethrins, pyrethroid exposure and asthma and allergies.
The chemical synthetic insecticide pyrethrins was usually served as a positive control; its mortality was taken from Yang et al.'s data with the same experimental methods [26].