Dermal toxicosis

Fenvalerate toxicity is antagonized by atropine sulfate or methocarbamol, which may be effective in treating severe cases of poisoning (Hiromori et al. 1986). Conversely, some compounds exacerbate the toxicity of fenvalerate and interfere with a desired use. Domestic cats (Felis domes-ticus) treated with Fendeet (an aerosol mixture of fenvalerate and A-A-diethyl-m-toluamide) to control fleas and ticks sometimes show signs of toxicosis, such as tremors, hypersalivation, ataxia, vomiting, depression, and seizures. Signs usually appeared within hours of topical application, and females and juveniles seem to be the most sensitive groups. The demonstrated ability of N-N-diethyl-m-toluamide to enhance the dermal absorption of fenvalerate is the probable cause of toxicosis (Dorman et al. 1990). 

Signs of famphur toxicosis in cattle include ataxia, muscular fasciculations, general weakness, lacrimation, salivation, and diarrhea. In comparison with European breeds of cattle (Bos taurus), the Brahman (Bos indicus) and European X Brahman hybrids are more sensitive to famphur, and Brahman bulls are more sensitive than cows. At a comparatively low famphur dose of 16.6 mg/kg BW, both B. taurus and B. indicus are tolerant of intramuscular injectable famphur however, B. indicus is more sensitive and bulls sometimes died when treatment levels exceeded 33.3 mg/kg BW. In addition to cattle, famphur-induced mortality in other species of mammals was documented. Single exposures of famphur in mg/kg BW killed rabbits (Oryctolagus sp.) at 2730.0 in dermal exposure mice (Mus sp.) at 27.0 in oral dose or 11.6 by intraperitoneal injection domestic sheep (Ovis aires) at 400.0 in oral dose and laboratory white rats (Rattus sp.) at 400.0 dermal exposure or >28.0 in oral dose. Mice receiving fatal or near-fatal intraperitoneal injections of famphur or famoxon began to convulse 10-20 min postinjection death came within 45 min post-injection, usually from respiratory failure. Mice remaining alive at 60 min post-injection usually recovered. 

Signs usually appeared within hours of topical application, and females and juveniles seem to be the most sensitive group. The demonstrated ability of N-N-diethyl-m-toluamide to enhance the dermal absorption of fenvalerate is the probable cause of toxicosis. 

Acute toxicosis is characterized by severe hemorrhagic gastroOTteritiS, dermal erythema, congested oral mucosae, dilated scleral blood vessels, arKl necrotizing pneumonia. 

Subacute or chronic toxicosis is characterized by chronic dermatitis, dermal necrosis, and peeiing of the epidermis. Subacute or chronic exposure can cause liver and kidney damage. 

---