Antivenin (Crotalidae) Polyvalent (ACP) has been the standard available treatment for copperhead bites. ACP is provided as dry powders and require reconstitution before administration. Reconstitution can take up to 60 minutes and should be initiated immediately when the patient arrives in the emergency department. ACP can be reconstituted by injecting 10 mL of supplied sterile water diluent into each vial and swirling (not shaking) to mix, or by diluting 10 vials of antivenin in 1 L of normal saline. The reconstituted antivenin (amount will vary, depending on amount required) is then diluted in 500 mL of normal saline or 5 percent dextrose in water, and a trial dose of 5 to 10 mL is administered intravenously over five minutes. If no reaction