Experimental induction and treatment of toad poisoning in the dog
Palumbo, N.E.; Perri, S.; Read, G.
Journal of the American Veterinary Medical Association 167(11): 1000-1005
1975
ISSN/ISBN: 0003-1488 PMID: 811632 Document Number: 88685
Toads of the species Bufo are widely distributed throughout the world and are poisonous. Their parotid glands contain bufotoxins which have an effect similar to that of digitalis and often cause ventricular fibrillation. Found also in bufotoxin are adrenaline, cholesterol, ergosterol and 5-hydroxytryptamide (5-HT). The highest biological concentration of 5-HT occurs in the skin of certain toads. Dogs which play with toads often grasp them in their mouths and, as well as obtaining toxin from the skin, they may compress the parotids. Experimental work reported in this paper indicated that intoxication from toads is probably by the glycoside part of the bufotoxin and may be potentiated by endogenous catecholamines. Treatment should be (in this order): decide if the history fits a diagnosis of toad poisoning; give 5 mg/kg propranolol i/v (blocks the beta-receptors of the adrenergic nerves); anaesthetize with pentobarbital, intubate and rinse the oral mucous membrane with water (to prevent further absorption of toxins); repeat propranolol in 20 minutes if needed; because propanolol causes massive leakage of K+ from RBCs, give potassium by slow i/v drip if this appears to be necessary, but this treatment should be monitored by ECG (lead II).