Digoxin immune FAB

Indications

Digoxin immune FAB is used for: Digoxin toxicity

Adult Dose

Acute Ingestion of Unknown Quantity Injection Administer 20 vials Larger dose has faster onset, but may cause febrile reaction; may give 10 vials initially, then at physician's discretion, administer 10 more vials Each vial of Fab (40 mg of Fab) binds 0.5 mg digoxin Equimolar dose to ingested digoxin (76/80 mg FAB = 1 mg digoxin) Acute Ingestion of Known Amount Total digoxin load (mg) divided by 0.5 mg digoxin bound per vial = number of vials to use Toxicity During Chronic Therapy Acute distress or for whom a serum digoxin concentration is not available: Administer 6 vials

Child Dose

Acute Ingestion of Unknown Quantity Injection As adults; administer 20 vials Larger dose has faster onset, but may cause febrile reaction; may give 10 vials initially, then at physician's discretion, administer 10 more vials; Small children: Monitor for volume overload Acute Ingestion of Known Amount As adults; total digoxin load (mg) divided by 0.5 mg digoxin bound per vial = number of vials to use Toxicity During Chronic Therapy Infants and small children (<20 kg): Administer 1 vial

Renal Dose

Renal Impairment Dose adjustment not necessary but use caution as digoxin immune Fab complex is renally eliminated

Administration

IV Preparation Reconstitute with 4 mL SWI to obtain a 9.5 mg/mL Digibind solution or 10 mg/mL Fab soln For infusion further dilute with NS to desired volume If very small doses are necessary (<3 mg), may dilute with NS to 1 mg/mL IV Administration Infuse over 15-30 min Fab should NOT be administered through filter May be given as rapid IVP if cardiac arrest is imminent (generally not recommended due to increased adverse reactions)

Contra Indications

Hypersensitivity to sheep proteins

Precautions

Serum digoxin levels rise after digibind treatment - do not use serum levels to guide continuing treatment Hypokalemia may occur from shifting of extracellular potassium to intracellular space; monitor closely Patients with heart failure may experience symptom exacerbation due to reduction in digoxin serum concentration Caution in patients with renal failure

Pregnancy-Lactation

Pregnancy Category: C Lactation: excretion in milk unknown; use with caution

Interactions

Adverse Effects

Side effects of Digoxin immune FAB : Frequency Not Defined Effects (due to w/d of digitalis) include exacerbation of HF, rapid ventricular response in patients with a.fib; posteral hypotension Falsely increases digoxin concentrations Hypokalemia Loss of disease control Phlebitis Fever, May occur with doses above 10 vials Allergic reactions Serum sickness

Mechanism of Action

Antibody binds digoxin or other cardiac glycosides and it is then excreted by the kidneys and removed from the body