Strychnine (Rodenticide) Flashcards
What is the most common poisoning with rodenticide?
malicious
recently banned (people will stock up)
why are cats rarely poisoning?
picky eaters
bitter taste
What forms does it come in?
treated grain bait
liquid
how toxic is it? to which animals?
all mammalian very toxic (even relay toxicity)
What is the absorption and distribution?
rapidly absorbed
not in specific tissue (in liver, kidney, blood, stomach contents
What is the metabolism and excretion?
metabolized by liver by N-oxidation
half life is 10h (total 24)
excreted in urine and saliva
What is the MOA?
nervous system at level of spinal cord and medulla
antagonizes glycine = loss of inhibitory process = excitation
K ion gates are altered resulting in motor neuron excitability
What are the clinical signs?
10 min onset
apprehension, nervousness, tenesmus and rigid muscles (face)
occasionally vomit
What are the characteristics of the convulsions?
TONIC
- extensor rigidity of all 4 legs (hyperreflexia)
- periods of relation between seizures
- as more toxin absorbed = seizures last longer and severity increases
- triggered my external stimuli
- ability to breathe becomes more impaired (death within 1-2h)
- anoxia causes pupils to dilate and become fixed
What are the PM findings?
no specific lesions
maybe trauma from seizures
agonal hemorrhage and congestion maybe
what is the Dx?
history of sudden onset of limb stiffness
analysis of stomach, vomitus or liver
What is the treatment?
emetic (apomorphine)
GL/AC/tannic acid (binding)
potassium permanganate (oxidizing agents added to lavage)
sedation
muscle relaxant (methocarbamol)
ammonium chloride to enhance urinary excretion
what is the Px?
if treated early usually within 1-2d
sore muscles for a while
What is the epidemiology?
dogs younger spring/fall multi-episode poisoning male large breeds
