Drug Detail:Digoxin (oral/injection) (Digoxin (oral/injection) [ di-jox-in ])
Drug Class: Group V antiarrhythmics Inotropic agents
Usual Adult Dose for Atrial Fibrillation
Total loading dose: Administer one-half the total loading dose initially (all formulations), then give one-fourth the total loading dose every 6 to 8 hours for two doses (IV and tablets), or give additional fractions every 4 to 8 hours (oral solution).
- IV: 8 to 12 mcg/kg
- Tablets: 10 to 15 mcg/kg
- Oral solution: 10 to 15 mcg/kg
Maintenance dose:
- IV: 2.4 to 3.6 mcg/kg once a day
- Tablets: 3.4 to 5.1 mcg/kg once a day
- Oral solution: 3.0 to 4.5 mcg/kg once a day
Comments:
- IM administration is not recommended due to associated pain and muscle necrosis. If IM administration is required, no more than 500 mcg of the injectable formulation should be injected into a single site.
- If rapid titration is desired, initiate with a loading dose followed by maintenance dosing; otherwise, initiate with maintenance dosing without a loading dose.
- Maintenance dose may also be estimated by the following formula: Total maintenance dose = loading dose x (% daily loss/100). For recommended maintenance doses according to lean body weight and renal function and additional definitions regarding maintenance dose calculation, the manufacturer product information should be consulted.
- Reduce dose in patients whose lean weight is an abnormally small fraction of total body mass (e.g., obesity, edema).
- Doses may be increased every 2 weeks according to clinical response, serum drug levels, and toxicity.
Uses:
- Treatment of mild to moderate heart failure in adults. Where possible, this drug should be used in combination with a diuretic and an angiotensin-converting enzyme (ACE) inhibitor.
- Control of ventricular response rate in patients with chronic atrial fibrillation.
Usual Adult Dose for Congestive Heart Failure
Total loading dose: Administer one-half the total loading dose initially (all formulations), then give one-fourth the total loading dose every 6 to 8 hours for two doses (IV and tablets), or give additional fractions every 4 to 8 hours (oral solution).
- IV: 8 to 12 mcg/kg
- Tablets: 10 to 15 mcg/kg
- Oral solution: 10 to 15 mcg/kg
Maintenance dose:
- IV: 2.4 to 3.6 mcg/kg once a day
- Tablets: 3.4 to 5.1 mcg/kg once a day
- Oral solution: 3.0 to 4.5 mcg/kg once a day
Comments:
- IM administration is not recommended due to associated pain and muscle necrosis. If IM administration is required, no more than 500 mcg of the injectable formulation should be injected into a single site.
- If rapid titration is desired, initiate with a loading dose followed by maintenance dosing; otherwise, initiate with maintenance dosing without a loading dose.
- Maintenance dose may also be estimated by the following formula: Total maintenance dose = loading dose x (% daily loss/100). For recommended maintenance doses according to lean body weight and renal function and additional definitions regarding maintenance dose calculation, the manufacturer product information should be consulted.
- Reduce dose in patients whose lean weight is an abnormally small fraction of total body mass (e.g., obesity, edema).
- Doses may be increased every 2 weeks according to clinical response, serum drug levels, and toxicity.
Uses:
- Treatment of mild to moderate heart failure in adults. Where possible, this drug should be used in combination with a diuretic and an angiotensin-converting enzyme (ACE) inhibitor.
- Control of ventricular response rate in patients with chronic atrial fibrillation.
Usual Pediatric Dose for Congestive Heart Failure
Total loading dose: Administer one-half the total loading dose initially (all formulations), then give one-fourth the total loading dose every 6 to 8 hours for two doses (IV and tablets), or give additional fractions every 4 to 8 hours (oral solution).
- Premature: IV: 15 to 25 mcg/kg; Oral solution: 20 to 30 mcg/kg
- Full-term: IV: 20 to 30 mcg/kg; Oral solution: 25 to 35 mcg/kg
- One month to 2 years: IV: 30 to 50 mcg/kg; Oral solution: 35 to 60 mcg/kg
- Two to five years: IV: 25 to 35 mcg/kg; Oral solution: 30 to 45 mcg/kg
- Five to ten years: IV: 15 to 30 mcg/kg; Oral solution: 20 to 35 mcg/kg; Tablets: 20 to 45 mcg/kg
- Greater than 10 to less than 18 years: IV: 8 to 12 mcg/kg; Oral solution: 10 to 15 mcg/kg; Tablets: 10 to 15 mcg/kg
Maintenance dose:
- Premature: IV: 1.9 to 3.1 mcg/kg twice a day; Oral solution: 2.3 to 3.9 mcg/kg twice a day
- Full-term: IV: 3 to 4.5 mcg/kg twice a day; Oral solution: 3.8 to 5.6 mcg/kg twice a day
- One month to 2 years: IV: 4.5 to 7.5 mcg/kg twice a day; Oral solution: 5.6 to 9.4 mcg/kg twice a day
- Two to five years: IV: 3.8 to 5.3 mcg/kg twice a day; Oral solution: 4.7 to 6.6 mcg/kg twice a day
- Five to ten years: IV: 2.3 to 4.5 mcg/kg twice a day; Oral solution: 2.8 to 5.6 mcg/kg twice a day; Tablets: 3.2 to 6.4 mcg/kg twice a day
- Greater than 10 to less than 18 years: IV: 2.4 to 3.6 mcg/kg once a day; Oral solution: 3 to 4.5 mcg/kg once a day; Tablets: 3.4 to 5.1 mcg/kg once a day
Comments:
- IM administration is not recommended due to associated pain and muscle necrosis. If IM administration is required, no more than 200 mcg of the injectable formulation should be injected into a single site.
- If rapid titration is desired, initiate with a loading dose followed by maintenance dosing; otherwise, initiate with maintenance dosing without a loading dose.
- Maintenance dose may also be estimated by the following formula: Total maintenance dose = loading dose x (% daily loss/100). For recommended maintenance doses according to lean body weight and renal function and additional definitions regarding maintenance dose calculation, the manufacturer product information should be consulted.
- Reduce dose in patients whose lean weight is an abnormally small fraction of total body mass (e.g., obesity, edema).
- Doses may be increased every 2 weeks according to clinical response, serum drug levels, and toxicity.
Use: To increase myocardial contractility in patients with heart failure.
Renal Dose Adjustments
For recommended maintenance doses according to lean body weight and renal function, the manufacturer product information should be consulted.
Liver Dose Adjustments
No adjustment recommended
Dose Adjustments
This drug should be used at the lowest effective dose in order to achieve therapeutic efficacy and minimize side effects.
Switching from IV to Oral: IV dose (mcg) x 1.25 = Oral dose (mcg)
Therapeutic drug monitoring/range: 0.5 to 2 ng/mL; some patients with atrial fibrillation may require 2 to 4 ng/mL.
Precautions
NARROW THERAPEUTIC INDEX:
- This drug should be considered a narrow therapeutic index (NTI) drug as small differences in dose or blood concentrations may lead to serious therapeutic failures or adverse drug reactions.
- Generic substitution should be done cautiously, if at all, as current bioequivalence standards are generally insufficient for NTI drugs.
- Additional and/or more frequent monitoring should be done to ensure receipt of an effective dose while avoiding unnecessary toxicities.
Safety and efficacy have not been established for the tablet formulation in patients younger than 5 years.
Consult WARNINGS section for additional precautions.
Dialysis
Data not available
Other Comments
Administration advice:
- Parenteral administration should be used only if rapid digitalization is needed or the drug cannot be tolerated orally.
- Inject over 5 minutes or longer and avoid bolus administration.
- If tuberculin syringes are used to measure very small doses, do not flush the syringe with the parenteral solution after the syringe contents are expelled into an indwelling vascular catheter to avoid over administration of digoxin.
Storage requirements: Protect from light.
Reconstitution/preparation techniques: May be administered undiluted or diluted with a 4-fold or greater volume of sterile water for injection, 0.9% sodium chloride injection, or 5% dextrose injection.
IV compatibility: Mixing with other drugs in the same container or simultaneous administration in the same IV line is not recommended.
General: In patients receiving diuretics with or without an angiotensin-converting enzyme (ACE) inhibitor, the withdrawal of this drug has been shown to result in clinical deterioration.
Monitoring:
- Drug toxicity: Serum levels of this drug just before the next scheduled dose or at least 6 hours after the last dose.
- Metabolic: Serum electrolytes periodically.
- Renal: Serum creatinine periodically.
Patient advice:
- Advise patients to contact their doctor or a health care professional if they experience nausea, vomiting, persistent diarrhea, confusion, weakness, or visual disturbances (including blurred vision, green-yellow color disturbances, halo effect) as these could be signs that the dose is too high.
- Advise parents or caregivers that the symptoms of digoxin toxicity in pediatric patients may include weight loss, failure to thrive in infants, abdominal pain, and behavioral disturbances.
- Instruct the patients to monitor and record their heart rate and blood pressure daily.
- For the oral solution, instruct patients to use the calibrated dropper and to avoid less precise measuring tools such as teaspoons. For doses less than 0.2 mL, provide another measuring syringe for accurate dosing, since the provided calibrated dropper is not appropriate to measure doses less than 0.2 mL.
- Instruct women of childbearing potential who become or are planning to become pregnant to consult a physician prior to initiation or continuing therapy with this drug.