title: Pyrethroid-induced paresthesia--a central or local toxic effect?
abstract: BACKGROUND
  Pyrethroid-induced paresthesia is frequently seen after dermal exposure to pyrethroids. Affected individuals experience a sensation of burning, tingling, itching, or numbness, most commonly in the face. This occurs 1-2 hours after the beginning of exposure and resolves spontaneously.
  
  
  RESULTS
  Paresthesia occurs as a result of a direct effect on intracutaneous nerve endings at very low pyrethroid doses. It is related to potency of the pyrethroid with pyrethroids without an alpha-cyano group generally showing the weakest effect.
  
  
  CONCLUSIONS
  Doses sufficient to cause paresthesia are far lower than those causing central or systemic toxicity. Paresthesia is therefore considered to be a localized nuisance effect. The best advice to affected individuals is to prevent paresthesia from occurring through appropriate hygiene measures and personal protection.
authors.affiliation: Medical Toxicology Unit, Guy's & St. Thomas' Hospital Trust, London, United Kingdom. Martin.Wilks@gstt.sthames.nhs.uk
authors.forename: M F
authors.initials: MF
authors.lastname: Wilks
mesh_terms: D000287:Administration, Topical; D000818:Animals; D004195:Disease Models, Animal; D006168:Guinea Pigs; D006801:Humans; D007306:Insecticides / Q000009:adverse effects*; D016273:Occupational Exposure / Q000009:adverse effects; D010292:Paresthesia / Q000139:chemically induced* / Q000503:physiopathology; D011722:Pyrethrins / Q000009:adverse effects*; D012867:Skin / Q000187:drug effects*
chemical_list: D007306:Insecticides; D011722:Pyrethrins