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Heart Failure in Adults
LANOXIN is indicated for the treatment of mild to moderate heart failure in adults. LANOXIN increases left ventricular ejection fraction and improves heart failure symptoms as evidenced by improved exercise capacity and decreased heart failure-related hospitalizations and emergency care, while having no effect on mortality. Where possible, LANOXIN should be used in combination with a diuretic and an angiotensin-converting enzyme (ACE) inhibitor.
Heart Failure in Pediatric Patients
LANOXIN increases myocardial contractility in pediatric patients with heart failure.
Atrial Fibrillation in Adults
LANOXIN is indicated for the control of ventricular response rate in adult patients with chronic atrial fibrillation.
DOSAGE AND ADMINISTRATION
Important Dosing Information
In selecting a LANOXIN dosing regimen, it is important to consider factors that affect digoxin blood levels (e.g., body weight, age, renal function, concomitant drugs) since toxic levels of digoxin are only slightly higher than therapeutic levels. Dosing can be either initiated with a loading dose followed by maintenance dosing if rapid titration is desired or initiated with maintenance dosing without a loading dose.
Consider interruption or reduction in digoxin dose prior to electrical cardioversion [see WARNINGS AND PRECAUTIONS].
Use digoxin solution to obtain the appropriate dose in infants, young pediatric patients, or patients with very low body weight.
Loading Dosing Regimen in Adults and Pediatric Patients
For adults and pediatric patients if a loading dosage is to be given, administer half the total loading dose initially, then ¼ the loading dose every 4 to 8 hours twice, with careful assessment of clinical response and toxicity before each dose. The recommended loading dose is displayed in Table 1.
Table 1: Recommended LANOXIN Oral Loading Dose
|Age||Oral Loading Dose, mcg/kg|
|5 to 10 years||20 -45|
|Adults and pediatric patients over 10 years||10-15|
|mcg = micrograms|
Maintenance Dosing in Adults and Pediatric Patients Over 10 Years Old
The maintenance dose is based on the lean body weight, renal function, age, and concomitant products [see DRUG INTERACTIONS].
The recommended starting maintenance dosage in adults and pediatric patients over 10 years old is displayed in Table 2. Doses may be increased every 2 weeks according to clinical response, serum drug levels, and toxicity.
Table 2: Recommended Starting
LANOXIN Maintenance Dosage in Adults and Pediatric Patients Over 10 Years Old
|Age||Oral Maintenance Dose, mcg/kg/day (given once daily)|
|Adults and pediatric patients over 10 years||3.4 – 5.1|
|mcg = micrograms|
Table 3 displays the recommended (once daily) maintenance dose of LANOXIN in pediatric patients over 10 years old and adult patients according to lean body weight and renal function. The doses are based on studies in adult patients with heart failure. Alternatively, the maintenance dose may be estimated by the following formula (peak body stores lost each day through elimination):
Total Maintenance Dose = Loading
Dose (i.e., Peak Body Stores) x % Daily Loss/100
(% Daily Loss = 14 + Creatinine clearance/5)
Reduce the dose of LANOXIN in patients whose lean weight is an abnormally small fraction of their total body mass because of obesity or edema.
Table 3: Recommended
Maintenance Dose (in micrograms given once daily) of LANOXIN in Pediatric
Patients Over 10 Years Old and Adults by Lean Body Weight and by Renal Functiona
|Corrected Creatinine Clearanceb||Lean Body Weightd||Number of Days Before Steady State Achievedc|
|aDoses are rounded to the nearest dose possible using whole
and/or half LANOXIN tablets. Recommended doses approximately 30 percent lower
than the calculated dose are designated with an *. Monitor digoxin levels in
patients receiving these initial doses and increase dose if needed. .
bFor adults, creatinine clearance was corrected to 70-kg body weight or 1.73 m² body surface area. If only serum creatinine concentrations (Scr) are available, a corrected Ccr may be estimated in men as (140 – Age)/Scr. For women, this result should be multiplied by 0.85.
For pediatric patients, the modified Schwartz equation may be used. The formula is based on height in cm and Scr in mg/dL where k is a constant. Ccr is corrected to 1.73 m² body surface area. During the first year of life, the value of k is 0.33 for pre-term babies and 0.45 for term infants. The k is 0.55 for pediatric patients and adolescent girls and 0.7 for adolescent boys.
GFR (mL/min/1.73 m²) = (k x Height)/Scr
cIf no loading dose administered.
dThe doses listed assume average body composition.
Maintenance Dosing in Pediatric Patients Less Than 10 Years Old
The starting maintenance dose for heart failure in pediatric patients less than 10 years old is based on the lean body weight, renal function, age, and concomitant products [see DRUG INTERACTIONS]. The recommended starting maintenance dose for pediatric patients between 5 and 10 years old with normal renal function is displayed in Table 4.
Table 4: Recommended Starting
LANOXIN Maintenance Dosage in Pediatric Patients Between 5 and 10 Years Old
|Age||Daily Oral Maintenance Dose, mcg/kg/day||Dose Regimen, mcg/kg/dose|
|5 to 10 years||6.4 – 12.9||3.2 – 6.4 Twice daily|
The recommended maintenance dose (to be given twice daily) is presented in Table 5.
Table 5: Recommended
Maintenance Dose (in micrograms given twice daily) of LANOXIN in Pediatric
Patients < 10 Years of Agea Based upon Lean Body Weight and Renal Functiona,b
|Corrected Creatinine Clearancec||Lean Body Weight||Number of Days Before Steady State Achievedd|
|aRecommended are doses to be given twice daily.
bThe doses are rounded to the nearest dose possible using whole and/or half LANOXIN tablets. Recommended doses approximately 30 percent lower than the calculated dose are designated with an *. Monitor digoxin levels in patients receiving these initial doses and increase dose if needed
c The modified Schwartz equation may be used to estimate creatinine clearance. See footnote b under Table 2.
d If no loading dose administered.
Monitoring to Assess Safety, Efficacy, and Therapeutic Blood Levels
Monitor for signs and symptoms of digoxin toxicity and clinical response. Adjust dose based on toxicity, efficacy, and blood levels.
Serum digoxin levels < 0.5 ng/mL have been associated with diminished efficacy, while levels above 2 ng/mL have been associated with increased toxicity without increased benefit.
Interpret the serum digoxin concentration in the overall clinical context, and do not use an isolated measurement of serum digoxin concentration as the basis for increasing or decreasing the LANOXIN dose. Serum digoxin concentrations may be falsely elevated by endogenous digoxin-like substances [see DRUG INTERACTIONS]. If the assay is sensitive to these substances, consider obtaining a baseline digoxin level before starting LANOXIN and correct post-treatment values by the reported baseline level.
Obtain serum digoxin concentrations just before the next scheduled LANOXIN dose or at least 6 hours after the last dose. The digoxin concentration is likely to be 10% to 25% lower when sampled right before the next dose (24 hours after dosing) compared to sampling 8 hours after dosing (using once-daily dosing). However, there will be only minor differences in digoxin concentrations using twice daily dosing whether sampling is done at 8 or 12 hours after a dose.
Switching from Intravenous Digoxin to Oral Digoxin
When switching from intravenous to oral digoxin formulations, make allowances for differences in bioavailability when calculating maintenance dosages (see Table 6).
Table 6: Comparison of the Systemic Availability and
Equivalent Doses of Oral and Intravenous LANOXIN
|Absolute Bioavailability||Equivalent Doses (in micrograms)|
|LANOXIN Tablets||60 -80%||62.5||125||250||500|
|LANOXIN Intravenous Injection||100%||50||100||200||400|
Dosage Forms And Strengths
Tablets: 125 micrograms are yellow, round, scored tablets with “Y3B” imprinted on one side. Tablets: 250 micrograms are white, round, scored tablets with “X3A” imprinted on one side.
Storage And Handling
LANOXIN (digoxin) Tablets, Scored 125 mcg (0.125 mg): Bottles of 100 with child-resistant cap (NDC 0173-0242-55) and 1,000 (NDC 0173-0242-75); unit dose pack of 100 (NDC 01730242-56). Imprinted with LANOXIN and Y3B (yellow).
LANOXIN (digoxin) Tablets, Scored 250 mcg (0.25 mg): Bottles of 100 with child-resistant cap (NDC 0173-0249-55), 1,000 (NDC 0173-0249-75), and 5,000 (NDC 0173-0249-80); unit dose pack of 100 (NDC 0173-0249-5656). Imprinted with LANOXIN and X3A (white).
Store at 25°C (77°F); excursions permitted to 15 to 30°C (59 to 86°F) in a dry place and protect from light. Keep out of reach of children.
Manufactured for : GlaxoSmithKline Research Triangle Park, NC 27709 by DSM Pharmaceuticals, Inc. Greenville, NC 27834 or GlaxoSmithKline Research Triangle Park, NC 27709. Revised: 08/2012
Last reviewed on RxList: 8/29/2012
This monograph has been modified to include the generic and brand name in many instances.
Additional Lanoxin Information
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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