Toads

Question 1

2 species of toads that cause intoxication

Answer 1

Cane or marine toad (Bufo marinus)

Colorado River toad (Bufo alvarius(

Question 2

Toxins from a toad are found in the

Answer 2

parotid gland

Question 3

Which toxins are involved in toad intoxication?

Answer 3

catecholamines and serotonin
bufotenine
bufagenins
bufotoxins
indole alkylamines

Question 4

Which toad toxin is a schedule I substance because it has a hallucinogenic effect?
A) Bufagenins
B) Bufotenine
C) Bufotoxins
D) None of the above

Answer 4

Bufotenine

Question 5

The two cardio active steroid toad toxins are
A) Bufagenins
B) Bufotenine
C) Bufotoxins
D) Indole Alkylamines

Answer 5

Bufotoxins and bufagenins - are similar to digitalis

Question 6

______ are similar to the hallucinogen LSD

Answer 6

Indole alkylamines

Question 7

Toxicity of toad poisons

Answer 7

dogs most susceptible, cats and ferrets can be poisoned
summer season
usually in the evening

Question 8

Toxicokinetics of toad toxins

Answer 8

toxins absorbed from MM of the mouth, gastric mucosa, conjunctiva and open skin wounds
distributed all over the body including CNS
catecholamines metabolized by MAO and COMT enzymes, undergo neuronal uptake
bufogenins excreted in urine

Question 9

MoA of toad toxicity

Answer 9

direct irritation of mucus membranes
main organs of toxicity are heart, blood vessels and CNS
bufogenins and bufotoxins have digitalis like effect by inhibiting Na/K ATPase
indole alkylamines have a hallucinogenic effect similar to LSD
bufotenine has vasoconstrictor effect and hallucinogenic effects

Question 10

Clinical signs of toad intoxication

Answer 10

start within a few minutes of exposure
irritation of MM - hyper salivation, red MM, vocalization and vomiting
neuro signs - disorientation, ataxia circling, seizures, opisthotonos, hyperthermia and coma
CV signs - tachypnea, tachycardia, cardiac arrhythmias, or bradycardia and collapse

Question 11

Lab diagnosis of toad toxicity

Answer 11

digoxin levels may be elevated

moderate increases in hemoglobin content, PCV, blood glucose, BUN, alkaline phosphatase, serum K, Ca and P

Question 12

Treatment of toad toxicity

Answer 12

flushing mouth with running water, activated charcoal, controlling seizures by diazepam, phenobarbital, propofol, glucocorticoids, furosemide, mannitol
atropine for bradycardia and as bronchodilator (not in tachycardia animals)
lidocaine and procainamide for ventricular arrhythmias
Digoxin immune Fab to bind bufagenins and bufotoxins
supportive care