warnings
WARNINGS Suicidal ingestion often involves more than one drug; thus, toxicity from other drugs should not be overlooked. One should consider the possibility of anaphylactic, hypersensitivity, or febrile reactions. If an anaphylactoid reaction occurs, the drug infusion should be discontinued and appropriate therapy initiated using aminophylline, oxygen, volume expansion, diphenhydramine, corticosteroids, and airway management as indicated. The need for epinephrine should be balanced against its potential risk in the setting of digitalis toxicity. Since the Fab fragment of the antibody lacks the antigenic determinants of the Fc fragment, it should pose less of an immunogenic threat to patients than does an intact immunoglobulin molecule. Patients with known allergies would be particularly at risk, as would individuals who have previously received antibodies or Fab fragments raised in sheep. Papain is used to cleave the whole antibody into Fab and Fc fragments, and traces of papain or inactivated papain residues may be present in DIGIBIND. Patients with allergies to papain, chymopapain, or other papaya extracts also may be particularly at risk. Skin testing for allergy was performed during the clinical investigation of DIGIBIND. Only one patient developed erythema at the site of skin testing, with no accompanying wheal reaction; this individual had no adverse reaction to systemic treatment with DIGIBIND. Since allergy testing can delay urgently needed therapy, it is not routinely required before treatment of life-threatening digitalis toxicity with DIGIBIND. Skin testing may be appropriate for high risk individuals, especially patients with known allergies or those previously treated with Digoxin Immune Fab (Ovine). The intradermal skin test can be performed by: Diluting 0.1 mL of reconstituted DIGIBIND (9.5 mg/mL) in 9.9 mL sterile isotonic saline (1:100 dilution, 95 mcg/mL). Injecting 0.1 mL of the 1:100 dilution (9.5 mcg) intradermally and observing for an urticarial wheal surrounded by a zone of erythema. The test should be read at 20 minutes. The scratch test procedure is performed by placing one drop of a 1:100 dilution of DIGIBIND on the skin and then making a ¼ -inch scratch through the drop with a sterile needle. The scratch site is inspected at 20 minutes for an urticarial wheal surrounded by erythema. If skin testing causes a systemic reaction, a tourniquet should be applied above the site of testing and measures to treat anaphylaxis should be instituted. Further administration of DIGIBIND should be avoided unless its use is absolutely essential, in which case the patient should be pretreated with corticosteroids and diphenhydramine. The physician should be prepared to treat anaphylaxis.