Crotalidae Immune F(Ab')2 (Equine)
Crotalidae Immune F(Ab')2 (Equine) is an antivenom used to treat envenomation from pit vipers including rattlesnakes, copperheads, and cottonmouths. It contains purified F(ab')2 antibody fragments derived from horse serum that bind to and neutralize venom toxins. This medication is indicated for patients with significant envenomation signs such as tissue swelling, coagulation abnormalities, or systemic symptoms.
An equine-derived antivenom that neutralizes pit viper venom to treat rattlesnake, copperhead, and cottonmouth envenomations.
Key facts at a glance
- RxNorm
- 2101270
- Generic
- Crotalidae Immune F(Ab')2 (Equine)
- Class
- pin-variant
- Brands
- Anavip
- Availability
- rx
- Lactation
- unknown
- Routes
- —
- Forms
- —
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Treatment of envenomation from Crotalidae pit vipers (rattlesnakes, copperheads, cottonmouths/water moccasins) when there is evidence of progressive tissue damage, coagulopathy, or systemic symptoms.
Equine-derived F(ab')2 antibody fragments bind to and neutralize venom components, preventing further tissue destruction, inhibiting coagulopathy, and allowing the body's immune system to clear the toxin-antibody complexes.
Contains horse protein and carries risk of hypersensitivity reactions and serum sickness. Must be administered intravenously. Dosing varies based on envenomation severity. Requires monitoring in a medical setting. May interfere with certain laboratory tests including crotalid venom detection assays.
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 27, 2026. · Read our editorial policy