Crotalidae polyvalent immune Fab

Crotalidae Polyvalent Immune Fab (Ovine) (CroFab) is a pharmaceutical drug used in the treatment of envenomations by North American crotalids, including rattlesnakes, copperheads, and cottonmouth/water moccasins. It is a type of antivenom that is derived from the immune response of sheep to the venom of these snakes. The product is a mixture of Fab fragments of immunoglobulin G (IgG), making it less likely to cause allergic reactions and serum sickness compared to older, whole-antibody antivenom preparations.

History

The development of Crotalidae Polyvalent Immune Fab (Ovine) marked a significant advancement in the treatment of venomous snake bites in North America. Prior to its introduction, treatments involved the use of whole IgG antivenoms, which were associated with a higher risk of adverse reactions. CroFab was approved by the Food and Drug Administration (FDA) in the United States in 2000, offering a safer alternative for patients.

Mechanism of Action

CroFab works by binding to the venom toxins of crotalid snakes, neutralizing their effects and facilitating their removal from the body. The Fab fragments are specifically designed to target and bind to the venom proteins, preventing them from causing damage to the body. This action reduces the severity of the envenomation and promotes recovery.

Indications

Crotalidae Polyvalent Immune Fab (Ovine) is indicated for the management of adult and pediatric patients with North American crotalid envenomation. The severity of the snake bite and the clinical symptoms of the patient determine the necessity and the dosage of the antivenom.

Administration

The administration of CroFab should be initiated as soon as possible after the snake bite to ensure the best possible outcome. The initial dose and subsequent doses are based on the clinical response of the patient. Continuous monitoring of the patient is necessary to adjust the treatment as needed.

Side Effects

While CroFab is generally well-tolerated, some patients may experience adverse reactions. Common side effects include rash, pruritus (itching), nausea, and back pain. Severe allergic reactions are rare but can occur, especially in individuals with known allergies to sheep proteins.