In most cases, these toxins aren't strong enough to discourage predators. But certain frogs in Central and South America have especially strong poisons in their skin. These frogs are called poison dart frogs, because native people used the poison from their skins on the tips of hunting arrows and blowdarts. There are about 170 different kinds of poison dart frogs. The most poisonous is the golden poison frog, each of which contains enough poison to kill eight people.
Toads make use of poison, too.
Behind their eyes they have a pair of poison glands, called parotoid glands. When the toad is threatened, a milky poisonous fluid oozes from the glands. The poison is stronger in some toads than others, but even in its mildest form it causes a burning sensation if it gets in the eyes or mouth of a predator. The stronger poisons can also cause muscle spasms, heartbeat irregularities, and breathing trouble. As terrifying as this may sound, it doesn't mean that you can't handle a toad.