Bromethalin was ingested by a Yorkie recently. It is a grain based bait. The block of poison was not in a bait station (box). The dog readily ate the end of the bait. The company that makes the poison confirmed there is no antidote. The poison kills by causing swelling in the brain with eventual paralysis and death. Luckily, we got the dog to throw up his stomach contents eliminating much of the ingested poison. We followed this with activated charcoal to bind the remaining poison. The dog survived due to early recognition of the poison and timely treatment.
PLEASE be careful with all rodent poisons. Place them where pets cannot get to them. Be especially careful Bromethalin as there is no antidote.