Frequently Asked Questions

• CroFab is a sheep-derived antivenom indicated for the management of adult and pediatric patients with North American crotalid envenomation. The term crotalid is used to describe the Crotalinae subfamily (formerly known as Crotalidae) of venomous
  snakes which includes rattlesnakes, copperheads, and cottonmouths/water moccasins.¹

• To order CroFab, please contact the BTG Specialty Solutions Center™ at 1-844-293-0007, or email CroFab@btgsp.com.

• The Unified Treatment Algorithm for the Management of North American Pit Viper Envenomation recommends administering
  CroFab when any of the following signs are present²:
  • Swelling that is more than minimal and that is progressing.
  • Hematologic venom effects, including elevated prothrombin time; decreased fibrinogen or platelets.
  • Any systemic signs attributable to venom (eg, hypotension, bleeding beyond the puncture site, refractory vomiting, diarrhea, angioedema, neurotoxicity).
• Learn more about the Unified Treatment Algorithm.

• Administer CroFab as soon as possible in patients who develop any signs of envenomation to prevent clinical deterioration.¹ In a clinical study, early administration of CroFab resulted in significantly shorter time to full recovery compared with later treatment.³
  Learn more about the efficacy of CroFab.

Yes! CroFab is the only antivenom derived from geographically and clinically relevant US snakes (ie, Western Diamondback
rattlesnake, Eastern Diamondback rattlesnake, Mojave rattlesnake, and cottonmouth or water moccasin), allowing for coverage of
all North American pit viper envenomations.^1,4

• The venom of North American pit vipers is complex and contains at least 50 different components, including clinically important
  cytotoxins, hemotoxins, and neurotoxins.^2,5,6 Each snake has a unique venomic fingerprint that is also influenced by
  environmental and individual factors.^7,8 According to the World Health Organization (WHO), an effective antivenom is one derived
  from clinically relevant snakes native to the geographic region in which the antivenom is used and collectively encompass the
  wide diversity of clinically relevant toxins in the same geographic region.⁴ CroFab is derived from 4 US snake species
  strategically chosen based on their unique venom fingerprints, which together provide comprehensive coverage across the
  diverse venom compositions of North American pit vipers.^1,9

• CroFab dosage requirements are contingent upon an individual patient’s response. Based on clinical experience with CroFab, the
  recommended initial dose is 4 to 6 vials; however, the starting dose may vary from a minimum of 4 vials to a maximum of 12
  vials based on clinical judgment and severity of envenomation.¹ An additional 4-6 vials should be administered if initial control is
  not achieved within 1 hour after the first dose.
  • Once initial control has been achieved, additional 2-vial doses of CroFab every 6 hours for up to 18 hours (3 doses) are recommended.¹

• Published clinical experience has not shown that a dosage adjustment for age should be made.¹ Antivenom dosing is based on neutralizing the dose of injected venom, and is titrated to clinical response, therefore CroFab dosing is the same for both
  pediatric and adult patients.^1,2

• Each batch of CroFab is tested for reconstitution time and must reconstitute in <7 minutes.⁹
  • Based on data from 72 batches of CroFab, the median time to reconstitute CroFab is 3 minutes.
• Learn more about the reconstitution of CroFab.

• Medically significant late bleeding is uncommon after treatment with CroFab.
  • In a systematic review of published postmarketing cohort studies, late bleeding was reported in 0.9% of patients (n=9/1017),
    and medically significant late bleeding was reported in 0.5% of patients (n=5/1017).¹⁰
  • In a report from the ACMT’s ToxIC NASBR from 2013-2015, major late bleeding complication occurred in 0.2% of patients (n=1/450).¹¹
• Learn more about the established safety profile of CroFab.

    ACMT, American College of Medical Toxicology; ToxIC, Toxicology Investigators Consortium; NASBR, North American Snakebite Registry. 

• CroFab is the only antivenom derived from geographically and clinically relevant US snakes for comprehensive coverage of all
  North American pit viper envenomations, including rattlesnakes, copperheads, and cottonmouths/water moccasins.^1,4

• Expert consensus guidelines recommend stocking CroFab at any facility that provide emergency care.¹²
  • The amount recommended to treat 1 patient for a period of 24 hours (hospitals admitting snakebite patients): 18 vials*
  • The amount recommended to treat 1 patient for a period of 8 hours (hospitals that stabilize and transfer snakebite patients):
    12 vials

*Physical stocking location may vary by institution and by drug preparation requirements.

• The most common adverse reactions (incidence ≥ 5% of subjects) reported in the clinical studies were urticaria, rash, nausea,
  pruritus, and back pain.¹