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Antivenin (Crotalidae) polyvalent

Generic name: antivenin (Crotalidae) polyvalent (AN tye VEN in (kroe TAL i dee) POL ee VAY lent)
Brand names: Anavip (equine), CroFab (ovine), Anavip, CroFab, Antivenin Polyvalent
Dosage form: intravenous powder for injection (-; crotalidae polyvalent (ovine))
Drug class: Antitoxins and antivenins

Medically reviewed by Drugs.com on Oct 4, 2023. Written by Cerner Multum.

What is antivenin (Crotalidae) polyvalent?

Antivenin (Crotalidae) is used in adults and children to treat symptoms of a snake bite from certain species of venomous snakes including rattlesnakes, copperheads, and cottonmouths (Water Moccasins).

Antivenin (Crotalidae) polyvalent may also be used for purposes not listed in this medication guide.

Antivenin (Crotalidae) polyvalent side effects

Get emergency medical help if you have signs of an allergic reaction: hives, difficult breathing, swelling of your face, lips, tongue, or throat.

Some side effects may occur during the injection. Tell your medical caregiver if you feel dizzy, nauseated, light-headed, itchy, sweaty, or have a headache, chest tightness, back pain, trouble breathing, or swelling in your face.

Antivenin (Crotalidae) polyvalent may cause serious side effects. Call your doctor at once if you have:

Common side effects of antivenin (Crotalidae) polyvalent may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Warnings

If you receive antivenin (Crotalidae) during an emergency, make sure any follow-up doctor knows you received antivenin (Crotalidae) polyvalent.

Before taking this medicine

You should not use antivenin (Crotalidae) if you are allergic to it, or if you have:

If possible during an emergency, tell your medical caregivers if you've ever had:

Antivenin (Crotalidae) is made from the blood or plasma of healthy horses or sheep. Blood and plasma are tested and treated to reduce the risk of it containing infectious agents, but there is still a small possibility it could transmit disease. Ask your doctor about your individual risk.

It is not known if antivenin (Crotalidae) will harm an unborn baby. Tell your doctor if you are pregnant.

It is not known whether antivenin (Crotalidae) passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breastfeeding.

If possible during an emergency, tell your medical caregivers if you are pregnant or breastfeeding.

Make sure any follow-up doctor knows you received this medicine.

How is antivenin (Crotalidae) polyvalent given?

You should receive antivenin (Crotalidae) as soon as possible after you first have symptoms of a snake bite (fang marks in the skin with swelling or redness and pain, blurred vision, sweating, increased salivation, vomiting, uncontrolled bleeding, trouble breathing, weakness, loss of muscle control, or numbness in the face or body).

Antivenin (Crotalidae) is injected into a vein by a healthcare provider.

You will be watched closely for at least 60 minutes after receiving the medicine to make sure you do not have an allergic reaction and your symptoms are improving.

You may need to receive additional doses if your symptoms do not improve after the first dose. Your doctor will determine how long to treat you with antivenin (Crotalidae).

Venom from a snake bite can increase your risk of bleeding, which can be severe or life-threatening. Call your doctor or seek emergency medical attention if you have any bleeding that will not stop.

Your doctor will monitor your progress and check for signs and symptoms of blood clots for 2 weeks or longer after you are treated with antivenin (Crotalidae). You may need to be treated again with antivenin (Crotalidae) and with a blood thinner.

Antivenin (Crotalidae) polyvalent dosing information

Usual Adult Dose for Venomous Snake Bite:

Initial dose: 4 to 6 vials, IV, over 60 minutes: at 25 to 50 mL/hour the first 10 minutes - if no allergic reaction, may increase rate to 250 mL/hour

Continue administering 4 to 6 vials, IV, over 60 minutes, every 6 hours for up to 18 hours, until initial control of envenomation is achieved

Maintenance dose (after initial envenomation control is achieved): 2 vials, IV, every 6 hours for up to 18 hours (3 doses); additional 2 vial doses may be given as deemed necessary based on the patient's clinical course

Comments:
-Administer as soon as possible after snakebite in patients with signs of progressive envenomation (e.g. worsening local injury, coagulation abnormality, or systemic envenomation signs).
-Early use (within 6 hours of snakebite) is advised to prevent clinical deterioration and systemic coagulation abnormalities.
-Closely monitor patients for allergic reactions during the infusion.
-Observe the patient for up to 1 hour after the first dose to determine if initial control has been achieved.

Usual Pediatric Dose for Venomous Snake Bite:

Initial dose: 4 to 6 vials, IV, over 60 minutes: at 25 to 50 mL/hour the first 10 minutes - if no allergic reaction, may increase rate to 250 mL/hour

Continue administering 4 to 6 vials, IV, over 60 minutes, every 6 hours for up to 18 hours, until initial control of envenomation is achieved

Maintenance dose (after initial envenomation control is achieved): 2 vials, IV, every 6 hours for up to 18 hours (3 doses); additional 2 vial doses may be given as deemed necessary based on the patient's clinical course

Comments:
-Administer as soon as possible after snakebite in patients with signs of progressive envenomation (e.g. worsening local injury, coagulation abnormality, or systemic envenomation signs).
-Early use (within 6 hours of snakebite) is advised to prevent clinical deterioration and systemic coagulation abnormalities.
-Closely monitor patients for allergic reactions during the infusion.
-Observe the patient for up to 1 hour after the first dose to determine if initial control has been achieved.

Anavip, CroFab

What happens if I miss a dose?

In an emergency medical setting, you are not likely to miss a dose.

What happens if I overdose?

In a medical setting an overdose would be treated quickly.

What should I avoid after receiving antivenin (Crotalidae) polyvalent?

Avoid activities that may increase your risk of bleeding or injury. Use extra care while shaving or brushing your teeth.

What other drugs will affect antivenin (Crotalidae) polyvalent?

Other drugs may affect antivenin (Crotalidae), including prescription and over-the-counter medicines, vitamins, and herbal products. Tell your doctor about all other medicines you use.

Does antivenin (crotalidae) polyvalent interact with my other drugs?

Enter medications to view a detailed interaction report using our Drug Interaction Checker.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.