Sr. Hansen et al., PYRETHRINS AND PYRETHROIDS IN DOGS AND CATS, The Compendium on continuing education for the practicing veterinarian, 16(6), 1994, pp. 707
Pyrethrin insecticides are derived from Chrysanthemum cinerariaefolium
and related species; pyrethroid insecticides are synthetic analogues
of pyrethrins. Both compounds are commonly incorporated in flea and ti
ck control products for dogs and cats. Pyrethrin and pyrethroid insect
icides reversibly increase the sodium conductance of nerves, resulting
in repetitive nerve discharges. Misuse or overuse of topical pyrethri
n products or use on an unusually sensitive dog or cat can produce cli
nical signs.