Item |
Information |
Drug Groups
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approved |
Description
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A cardiotonic glycoside obtained mainly from Digitalis lanata; it consists of three sugars and the aglycone digoxigenin. Digoxin has positive inotropic and negative chronotropic activity. It is used to control ventricular rate in atrial fibrillation and in the management of congestive heart failure with atrial fibrillation. Its use in congestive heart failure and sinus rhythm is less certain. The margin between toxic and therapeutic doses is small. (From Martindale, The Extra Pharmacopoeia, 30th ed, p666) |
Indication |
For the treatment and management of congestive cardiac insufficiency, arrhythmias and heart failure. |
Pharmacology |
Digoxin, a cardiac glycoside similar to digitoxin, is used to treat congestive heart failure and supraventricular arrhythmias due to reentry mechanisms, and to control ventricular rate in the treatment of chronic atrial fibrillation. |
Toxicity |
Toxicity includes ventricular tachycardia or ventricular fibrillation, or progressive bradyarrhythmias, or heart block. LD50 = 7.8 mg/kg (orally in mice). |
Affected Organisms |
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Humans and other mammals |
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Biotransformation |
Hepatic (but not dependent upon the cytochrome P-450 system). The end metabolites, which include 3 b-digoxigenin, 3-keto-digoxigenin, and their glucuronide and sulfate conjugates, are polar in nature and are postulated to be formed via hydrolysis, oxidation, and conjugation. |
Absorption |
Absorption of digoxin from the elixir pediatric formulation has been demonstrated to be 70% to 85% complete (90% to 100% from the capsules, and 60% to 80% for tablets). |
Half Life |
3.5 to 5 days |
Protein Binding |
25% |
Elimination |
Following intravenous administration to healthy volunteers, 50% to 70% of a digoxin dose is excreted unchanged in the urine. |
References |
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Thompson DF, Carter JR: Drug-induced gynecomastia. Pharmacotherapy. 1993 Jan-Feb;13(1):37-45.
[Pubmed]
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Doering W, Konig E, Sturm W: [Digitalis intoxication: specifity and significance of cardiac and extracardiac symptoms. part I: Patients with digitalis-induced arrhythmias (author's transl)] Z Kardiol. 1977 Mar;66(3):121-8.
[Pubmed]
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Kaplanski J, Weinhouse E, Topaz M, Genchik G: Verapamil and digoxin: interactions in the rat. Res Commun Chem Pathol Pharmacol. 1983 Dec;42(3):377-88.
[Pubmed]
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Flanagan RJ, Jones AL: Fab antibody fragments: some applications in clinical toxicology. Drug Saf. 2004;27(14):1115-33.
[Pubmed]
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External Links |
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