Crotalidae polyvalent immune FAB (ovine) (CroFab, Copperhead Antivenom (Immune FAB), Cottonmouth Antivenom (Immune FAB), Diamondback Antivenom (Immune FAB), Fab Crotalidae polyval AD, Rattlesnake Antivenom (Immune FAB), Sidewinder Antivenom (Immune FAB), Water Moccasin Antivenom (Immune FAB))
Classes: Antivenins
- Dosing and uses of CroFab, Copperhead Antivenom (Immune FAB) (Crotalidae polyvalent immune FAB (ovine))
- CroFab, Copperhead Antivenom (Immune FAB) (Crotalidae polyvalent immune FAB (ovine)) adverse (side) effects
- Warnings
- Pregnancy
- Pharmacology of CroFab, Copperhead Antivenom (Immune FAB) (Crotalidae polyvalent immune FAB (ovine))
- Administration
Dosing and uses of CroFab, Copperhead Antivenom (Immune FAB) (Crotalidae polyvalent immune FAB (ovine))
Adult dosage forms and strengths
powder for injection
- Up to 1g/vial (ovine antiserum)
Envenomation
Indicated for North American crotalid envenomation by Crotalinae rattlesnakes (eg, cottonmouths/water moccasins, copperheads, rattlesnakes)
InitiaL
- Begin treatment as soon as possible (ideally within 6 hr of snakebite) in patients who develop signs of progressive envenomation including worsening local injury, coagulation abnormality, or systemic signs of envenomation
- Start with 4-6 vials/dose IV infused over 1 hr; monitor for 1 hr following infusions for allergic reaction; repeat with additional 4-6 vials if control not achieved with initial dose
- Repeat with 4-6 vials/dose until local tenderness/swelling not significantly progressing, coagulation tests and systemic signs trend toward normal
- Supportive measures for manifestations of envenomation, such as pain, swelling, hypotension, and wound infection
Maintenance
- Maintenance antivenom therapy may be indicated
- Once control achieved, may need to administer 2 vials IV q6hr for up to 18 hr; optimal dosing past 18 hr not established; however, treatment may be continued based on patient contition
Pediatric dosage forms and strengths
powder for injection
- Up to 1g/vial (ovine antiserum)
Envenomation
Indicated for North American crotalid envenomation by Crotalinae rattlesnakes (eg, cottonmouths/water moccasins, copperheads, rattlesnakes)
The absolute venom dose following snakebite is expected to be the same in children and adults, and therefore, no dosage adjustment for age should be made
InitiaL
- Begin treatment as soon as possible (ideally within 6 hr of snakebite) in patients who develop signs of progressive envenomation including worsening local injury, coagulation abnormality, or systemic signs of envenomation
- Start with 4-6 vials/dose IV infused over 1 hr; monitor following infusions for allergic reaction; repeat with additional 4-6 vials if control not achieved with initial dose
- Repeat with 4-6 vials/dose IV until local local tenderness/swelling not significantly progressing, coagulation tests and systemic signs trend toward normal
- Supportive measures for manifestations of envenomation, such as pain, swelling, hypotension, and wound infection
Maintenance
- Maintenance antivenom therapy may be indicated
- Once control achieved, may need to administer 2 vials IV q6hr for up to 18 hr; optimal dosing past 18 hr not established; however, treatment may be continued is determined to be necessary based on patient condition
CroFab, Copperhead Antivenom (Immune FAB) (Crotalidae polyvalent immune FAB (ovine)) adverse (side) effects
Frequency not defined
Pruritus
Rash
Urticaria
Hypotension
Chills
Fever
Anorexia
Nausea
Asthma
Cough
Dyspnea
Wheezing
Anaphylaxis
Anaphylactoid reaction
>10%
Hypersensitivity reactions (5-19%)
1-10%
Serum sickness (5%)
<1%
Angioedema
Chest discomfort
Dizziness
Erythema
Headache
Hyperhydrosis
Lip swelling
Musculoskeletal chest pain
Tachycardia
Tachypnea
Tongue swelling
Tracheal edema
Postmarketing reports
Delayed allergic reaction manifested by fever, pruritus and/or rash
Delayed or recurrent coagulopathy or thrombocytopenia
Failure to achieve intial controL
Recurrent swelling refractory to treatment
Thrombocytopenia refractory to treatment
Prolonged hospitalization
Bleeding
Nausea
Tremor
Worsening eye sight
Treatment failure resulting in death
Warnings
Contraindications
(Relative) History of hypersensitivity to papaya or papain unless benefits outweigh risks and appropriate anaphylaxis treatment is readily available
Cautions
Contains up to 30 mcg of ethyl mercury from thimerosal or approximately 0.03 mg of mercuary per vial or no more than 0.6 mg of mercuary per dose
If patient develop coagulopathy, due to snakebite, monitor for recurrent coagulopathy for up to 1 week or longer
Monitor for anaphylaxis and hypersensitivity reactions; patients with allergies to papain, chymopapain, other papaya extracts, or the pineapple enzyme bromelain may be at risk for hypersensitivity reaction
Use treatment within 4-6 hr of envenomation to prevent clinical deterioration and development of coagulation abnormalities
Pregnancy and lactation
Pregnancy category: C
Lactation: Excretion in milk unknown; use with caution
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of CroFab, Copperhead Antivenom (Immune FAB) (Crotalidae polyvalent immune FAB (ovine))
Mechanism of action
Venom-specific Fab fragment of immunoglobulin G (IgG) that works by binding and neutralizing the venom toxins and facilitate their redistribution away from the target tissue and their elimination from the body
Absorption
Onset: Within 1 hr of administration
Distribution
Vd (total Fab): 300 mL/kg
Elimination
Systemic clearance: 32 mL/min (approximately 0.4 mL/min/kg)
Half-life: 12-23 hr
Administration
IV Preparation
Inspect visually for particulate matter and discoloration prior to administration
Reconstitute each vial in 18 mL of 0.9% saline and mix; do not shake
Further dilute content of reconstituted vials in 250 mL of 0.9% NaCl; mix gently
Use within 4 hr of reconstitution
IV Administration
IV infusion over 60 min
Infuse slowly over first 10 min at 25-50 mL/hr rate with careful observation for allergic reaction
If no allergic reaction, increase infusion rate to 250 mL/hr
Administer within 6 hr of snakebite advised
Storage
Refrigerate virgin vials, don't freeze