CroFab

CroFab is the commercial name for a snake antivenin, crotalidae polyvalent immune fragment antigen binding, manufactured by Savage Laboratories in Melville, New York. It is one of several antivenins available for the treatment of North American rattlesnake and cottonmouth bites.

It is made by immunizing healthy sheep to one of the following four venomous snake species: Crotalus atrox (western diamondback rattlesnake), Crotalus adamanteus (eastern diamondback rattlesnake), Crotalus scutulatus (Mojave rattlesnake), and Agkistrodon piscivorus (cottonmouth). Then the antibodies are extracted from the blood, purified, and mixed together to include the antibodies from all four different venoms used. Finally the serum is freeze dried for distribution and storage. Each vial contains 1g of the antibodies in sodium phosphate as a buffering agent and thiomersal as a preservative. The product is intended for intravenous use after being reconstituted with water and is only commonly available to hospitals, not by a typical doctor's prescription.