Digoxin specific antibody (Fab) fragments in 34 cases of severe digitalis intoxication

34 patients aged between 2 and 80 years were treated with digoxin specific antibody (Fab) fragments for severe digitalis poisoning. In 27 cases, the glycoside was taken with suicidal intent; in 3 cases accidentally and 4 were iatrogenic. The following criteria were considered to be indications for use of Fab fragments: the appearance of life-threatening arrhythmias such as high-grade atrioventricular conduction disorders (grade 2 and 3 A-V block), multifocal ectopic beats, ventricular tachycardia, and relapsing ventricular fibrillation. Serum digoxin concentrations were between 3.4 and 29ng/ml before the start of treatment. Between 240 and 800mg of Fab were administered; the majority of patients received 480mg. Regression of arrhythmias was seen between 0.5 and 8 hours after Fab infusion. There was a rapid fall in the free digoxin in the serum to concentrations that were no longer measurable and a marked rise in bound digoxin with a simultaneous increase of excretion of bound digoxin in the urine. Fab therapy is considered to be a major advance in the treatment of severe, previously fatal, glycoside poisoning. No notable side effects or allergic reactions were observed.