Insecticides Flashcards
main source of exposure with Pyrethrins and Pyrethroids
Use of canine “spot-on” products on cats
mechanism of action of Pyrethrins and Pyrethroids
Delay closure of Na channels
“Knockdown effect” - rapid paralysis caused by inhibition of neurons
Interfere with GABA at ↑ concentrations
Stim. adrenals - hyperglycemia
clinical signs Pyrethrins and Pyrethroids
Generalized muscle tremors, depression, blindness, ataxia
Salivation, V+/D+ hyperexcitability
May progress to seizures, dyspnea, death
treatment of Pyrethrins and Pyrethroids
No specific antidote, Decontamination - wash skin; Monitor and control temp. Methocarbamol - muscle tremors; Diazepam, barbiturates, propofol CRI- seizures
T/F activated charcoal is generally not used with Pyrethrins and Pyrethroids
True
T/F the MoA of DEET is unknown
true
clinical signs with DEET
Hypersalivation, vomiting, hyperexcitability, tremors, ataxia, seizures
treatment of DEET
No specific antidote;
Decontamination: wash skin, emesis, activated charcoal +/- cathartic: AVOID-Mg, may cause CNS depression
Symptomatic treatment
MoA of Amitraz
α2-agonist, weak α1-agonist, weak MAO inhibitor
clinicals signs with Amitrz
Transient sedation, Lethargy, ataxia, bradycardia, depression, V+, dyspnea, hypothermia, tremors, seizures, CV collapse and resp. failure, Hyperglycemia
treatment of Amitraz
Yohimbine/ Atipamezole - α2-antagonist,
Decontamination - wash with soap/water; emesis, activated charcoal, supportive care
DDx Amitraz
other CNS depressants (ethanol, ivermectin, ethylene glycol, marijuana)
MoA of ivermectin
GAGA agonist - CNS suppression
common exposure routes with ivermectin
extra-label use
ingestion of horse feces
Clinical signs: ivermectin
CNS depression - disorientation, stupor, ataxia, hyperesthesia, hypersalivation, vocalization, progressive weakness→ recumbency, coma, death
Pos. muscle fasciculation, tremors
treatment: ivermectin
No specific antidote;
Decontamination - emesis, activated charcoal: repeat q8h for 2 days, extrahepatic circulation
Physostigmine (cholinesterase inhibitor)
Flumazenil, Picrotoxin (GABA antagonist)
T/F collie breeds can have a ABCB1-1Δ/MDR1 gene mutation that make them susceptible to ivermectin toxiciosis
True
drug crosses blood brain barrier - “white feet, don’t treat”
T/F ivermectin is excreted unchanged in the feces
True
why some dogs can be exposed to toxic amounts via ingestion of horse feces
