Ask a Dog Vet and Get Answers to Your Dog Veterinary Questions
I am sorry to hear about your dog getting a toad. My name is Rebecca. I am a veterinarian and will do my best to help.
The first thing to do is rinse out his mouth right away, to flush out any toad toxin still in his mouth.
With toads, often all that is seen is this reaction to the toxin in the mouth: smacking the lips, spitting out saliva. In some cases, if enough toxin is absorbed (so the sooner you rinse the mouth the better) there can be other side effects such as tremors or seizures. With cane toads, the heart can be affected. If you are sure it is a cane toad ( where in the US do you live?) you might want to take him to emergency to have his heart monitored.
Let me know how he is doing and what else I can answer.
I hope you were able to see my answer; how is he doing?