antitoxins

Antitoxins are preparations that contain antibodies or other neutralizing agents capable of inactivating toxins produced by bacteria, plants, or venoms. They provide immediate, short-term protection by transferring passive immunity to the recipient. Historically, many antitoxins were derived from the sera of immunized animals (such as horses or sheep) that were then processed into therapeutic products. More recently, human-derived immunoglobulins and monoclonal antibodies have been developed to target specific toxins. Examples used in clinical practice include tetanus immune globulin and diphtheria antitoxin, as well as botulism immune globulin and botulism antitoxins, depending on the toxin and patient age. For infant botulism, human-derived botulism immune globulin is used, while in older patients equine-derived botulism antitoxins may be employed under medical supervision.

Mechanism of action involves binding to free toxin in the circulation or extracellular space, preventing the toxin from attaching to host cell receptors or from exerting its enzymatic effect. By neutralizing circulating toxin, antitoxins can halt progression of toxicity if given early. They do not reverse damage already caused within cells and generally do not confer long-lasting immunity; their effect is temporary.

Administration and safety considerations include delivery by injection or infusion in a controlled setting. Because many products are derived from animal sources, hypersensitivity reactions and anaphylaxis are potential risks; modern preparations favor human or humanized antibodies to reduce such reactions. Storage requires appropriate cold-chain conditions, and availability varies by toxin and region.

Limitations and context: early administration improves outcomes, but vaccination with toxin-toxoids remains the primary preventive strategy against disease. Antitoxins are used as part of treatment regimens, often alongside other therapies and supportive care. They are distinct from antivenoms, which neutralize venoms rather than bacterial or plant toxins.