Why do poison dart frogs eat poisonous insects and don't die

poison dart frogs have also evolved resistance to their own toxins,but through a different mechanism.These tiny animals defend themselves using hundreds of bitter-tasting compounds called alkaloids that they accumulate from consuming small arthropods like mites and ants.One of their most potent alkaloids is the chemical epibatidine,which binds to the same receptors in the brain as nicotine but is at least ten times stronger.An amount barely heavier than a grain of sugar would kill you.So what prevents poison frogs from poisoning themselves?