Cardiovascular Medicine Book

Congestive Heart Failure

Coronary Artery Disease

Electrocardiogram

Examination

Hyperlipidemia

Hypertension

Miscellaneous

Pericardial Disorders

Obstetrics Chapter related topics

http://www.fpnotebook.com/

DigoxinAka: Lanoxin, Digitalis, Digitalis Glycoside

Advertisement

  1. History
    1. Derived from Foxglove (Digitalis) plant
    2. Originally used as herbal tea to cure "Dropsy"
    3. Best described by William Withering, England, 1775
  2. Mechanism
    1. Inotropic effect (Increases myocardial contractility)
      1. Inhibits membrane-bound sodium potassium ATPase
        1. Increases calcium in sarcoplasmic reticulum
        2. Increases myocardial contractility
      2. Not affected by Beta Adrenergic Receptor antagonist
        1. Not dependent on endogenous Catecholamines
      3. Less Potent than parenteral inotropes
    2. Sinoatrial node and Atrioventricular Node effects
      1. Accelerates atrial conduction
      2. Depresses conduction through AV node
  3. Indications
    1. Paroxysmal Supraventricular Tachycardia (PSVT)
      1. Hemodynamically stable patient
      2. Conversion to Normal Sinus Rhythm
    2. Chronic Congestive Heart Failure (Systolic Dysfunction)
    3. Atrial Fibrillation or Atrial Flutter
      1. Second line agent for Ventricular rate control
      2. Use in reduced ejection fraction
  4. Contraindications
    1. Avoid in Diastolic Dysfunction
  5. Drug Interactions
    1. Medications that increase Digoxin concentration
      1. Quinidine
      2. Verapamil
      3. Diltiazem
      4. Amiodarone
      5. Carvedilol
      6. Omeprazole (Prilosec)
      7. Propafenone
      8. Spironolactone (may yield falsely elevated levels)
    2. Medications that decrease Heart Rate and AV Conduction
      1. Verapamil
      2. Diltiazem
      3. Amiodarone
      4. Beta Blockers
      5. Propafenone
      6. Sotalol
    3. Medications that decrease Digoxin absorption
      1. Antacids (space administration 2 hours apart)
      2. Cholestyramine
      3. Colestipol
  6. Pharmacokinetics
    1. Effects following intravenous dose
      1. Onset
        1. Intravenous: 5 to 30 minutes
        2. Oral: 30 minutes to 2 hours
      2. Peak: 1.5 to 3 hours
    2. Half-Life: 36 hours
  7. Dose
    1. Indications to lower digoxin dose by 50%
      1. Drug interactions (see above)
      2. Severe renal insufficiency (0.0625 mg daily)
    2. Chronic Congestive Heart Failure
      1. Dose: 0.125 mg po daily
    3. Rapid Atrial Fibrillation
      1. Load
        1. First Dose: 0.5 mg IV
        2. Second and Third Dose: 0.25 mg IV q6h for 2 doses
      2. Maintenance
        1. Dose: 0.125 to 0.375 mg IV or PO qd
  8. Efficacy: Congestive Heart Failure (Stages C and D)
    1. Low doses (0.125 mg qd) are effective
      1. Digoxin Serum level 0.5 to 1.0 ng/ml
      2. Reduced morbidity
      3. Reduced Congestive Heart Failure signs and symptoms
      4. Neutral effect on mortality
      5. No benefit in acute Congestive Heart Failure
    2. RADIANCE trial (supports continued use of Digoxin)
      1. Packer (1993) N Engl J Med 329:1
      2. Smith (1993) N Engl J Med 329:51
  9. Efficacy: Atrial Fibrillation
    1. Not a great drug for rate control with activity
    2. Delayed onset of action
    3. Not first line for emergent rapid Atrial Fibrillation
  10. Precautions
    1. Chronic Congestive Heart Failure
      1. Do not need to routinely follow Digoxin levels
      2. Check level if signs Digoxin Toxicity
    2. Acute management
      1. High Digoxin Toxicity risk in critically ill patient
      2. Parenteral inotropes are preferred over digoxin
        1. More potent
        2. Less toxicity

Digitalis Glycosides (C0012253)

Definition (MSH)Glycosides from plants of the genus DIGITALIS. Some of these are useful as cardiotonic and anti-arrhythmia agents. Included also are semi-synthetic derivatives of the naturally occurring glycosides. The term has sometimes been used more broadly to include all CARDIAC GLYCOSIDES, but here is restricted to those related to Digitalis.
ConceptsCarbohydrate (T118) , Pharmacologic Substance (T121)
MSHD004071
EnglishDigitalis glycoside, Digitalis Glycosides
Spanishglucosido digitalico
Parent ConceptsCardiac Glycosides (C0007158), Cardenolides (C0007143), Cardiovascular Agents (C0007220)
SourcesAOD, MSH, MTH, NDFRT, SCTSPA, SNOMEDCT, VANDF
Derived from the NIH UMLS (Unified Medical Language System)


Digoxin (C0012265)

Definition (MSH)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)
Definition (CSP)cardiotonic glycoside obtained mainly from Digitalis lanata; it consists of three sugars and the aglycone digoxigenin; digoxin has positive inotropic and negative chronotropic activity; 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.
Definition (PDQ)A cardiac glycoside. Digoxin inhibits the sodium potassium adenosine triphosphatase (ATPase) pump, thereby increasing intracellular calcium and enhancing cardiac contractility. This agent also acts directly on the atrioventricular node to suppress conduction, thereby slowing conduction velocity. Apparently due to its effects on intracellular calcium concentrations, digoxin induces apoptosis of tumor cells via a pathway involving mitochondrial cytochrome c and caspases 8 and 3. Check for "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=485249&idtype=1" active clinical trials or "http://www.cancer.gov/Search/ClinicalTrialsLink.aspx?id=485249&idtype=1&closed=1" closed clinical trials using this agent. ("http://nciterms.nci.nih.gov:80/NCIBrowser/ConceptReport.jsp?dictionary=NCI_Thesaurus&code=C28990" NCI Thesaurus)
Definition (NCI)A cardiac glycoside. Digoxin inhibits the sodium potassium adenosine triphosphatase (ATPase) pump, thereby increasing intracellular calcium and enhancing cardiac contractility. This agent also acts directly on the atrioventricular node to suppress conduction, thereby slowing conduction velocity. Apparently due to its effects on intracellular calcium concentrations, digoxin induces apoptosis of tumor cells via a pathway involving mitochondrial cytochrome c and caspases 8 and 3. (NCI04)
ConceptsSteroid (T110) , Carbohydrate (T118) , Pharmacologic Substance (T121)
MSHD004077
EnglishDigoxin, Digoxin - chemical, DIGOXIN PREPARATION, Digoxin product
Spanishdigoxina
Parent ConceptsCardiac Glycosides (C0007158), Cardenolides (C0007143), Digitalis Glycosides (C0012253), Unclassified Chemotherapy Agent (C1519763), Class IV antiarrhythmic drug (C0360706), Duplicate concept (C1274013), Direct Cardiac Inotropics (C1579439)
SourcesCSP, LCH, LNC, MSH, MTH, MTHSPL, NCI, NDFRT, PDQ, RXNORM, SCTSPA, SNOMEDCT, USPMG, VANDF
Derived from the NIH UMLS (Unified Medical Language System)


Digitalis preparation (C0304520)

Definition (CSP)extract from genus of toxic herbaceous Eurasian plants of the Scrophulaceae which yield cardiotonic digitalis glycosides; most useful species are Digitalis lanata and D. purpurea.
ConceptsOrganic Chemical (T109) , Pharmacologic Substance (T121)
EnglishDigitalis, Digitalis extract, Digitalis preparation
Spanishdigital, extracto digitalico, preparado digitalico
Parent ConceptsPlant Extracts (C0032081), Cardiac Glycosides (C0007158), Natural Products (C1566558), Digitalis Glycosides (C0012253), Unclassified Ingredients (C1372954), Digoxin (C0012265), Plant cardiac glycoside (C0303994)
SourcesCSP, MTH, NCI, NDFRT, RXNORM, SCTSPA, SNOMEDCT, VANDF
Derived from the NIH UMLS (Unified Medical Language System)


Lanoxin (C0699988)

ConceptsSteroid (T110) , Carbohydrate (T118) , Pharmacologic Substance (T121)
MSHD004077
EnglishGlaxo Wellcome Brand of Digoxin, GlaxoSmithKline Brand 1 of Digoxin, Lanoxin, Lanoxin PG, Lanoxin-PG, Lenoxin, Virco Brand of Digoxin
SourcesMSH, NCI, PDQ, RXNORM
Derived from the NIH UMLS (Unified Medical Language System)



Navigation Tree