What term describes a substance that neutralizes or counteracts poisoning?

The term that describes a substance that neutralizes or counteracts poisoning is known as an antidote. Antidotes work by either binding to the toxic substance, thereby preventing it from exerting its harmful effects, or by reversing the physiological effects induced by the poison. This can be crucial in emergency medical situations where timely intervention can save a patient's life or reduce the severity of poisoning.

In contrast, antivenin specifically refers to a type of antidote used to treat venomous bites or stings from animals, such as snakes or spiders, and is not used for all types of poisoning. Antibiotics are medications used to treat bacterial infections, not poisons, while antifungals are used to treat fungal infections. Thus, while all of these terms involve medical treatments, only antidote encompasses the broader category of counteracting poisons.