LANOXIN PEDIATRIC
Clinical safety rating: caution
Comprehensive clinical and safety monograph for LANOXIN PEDIATRIC (LANOXIN PEDIATRIC).
Inhibition of Na+/K+ ATPase leading to increased intracellular calcium and positive inotropy.
| Metabolism | Hepatic via glucuronidation; substrate of P-glycoprotein; renal excretion of unchanged drug. |
| Excretion | Renal excretion of unchanged drug accounts for 60-80% of elimination; nonrenal clearance is 20-40% (biliary/fecal). |
| Half-life | Terminal elimination half-life is 36-48 hours in adults with normal renal function; prolonged to 3.5-5 days in anephric patients due to reduced renal clearance. |
| Protein binding | 20-30% bound to plasma proteins, primarily albumin. |
| Volume of Distribution | Vd is 5-10 L/kg in adults, indicating extensive tissue binding; higher in infants (up to 16 L/kg) with reduced protein binding. |
| Bioavailability | Oral: 60-80% (Lanoxin Pediatric elixir 70-85%); variable due to first-pass metabolism and P-glycoprotein effects. |
| Onset of Action | IV: 5-30 minutes; Oral: 0.5-2 hours. |
| Duration of Action | Duration of clinical effect is 3-6 days, correlating with tissue (myocardial) binding; cardiac effects persist after serum levels decline. |
| Molecular Weight | 781 |
Adult: Oral loading dose 0.75-1.5 mg in divided doses over 24-48 hours. Maintenance: 0.125-0.5 mg once daily. Intravenous: Loading dose 0.5-1 mg over 10-20 minutes, then maintenance 0.125-0.5 mg once daily.
| Dosage form | INJECTABLE |
| Renal impairment | GFR >50 mL/min: no adjustment; GFR 10-50 mL/min: reduce dose by 25-50%; GFR <10 mL/min: reduce dose by 50-75% or consider alternative. |
| Liver impairment | Child-Pugh A: no adjustment; Child-Pugh B: reduce dose by 25-50%; Child-Pugh C: avoid use or reduce dose by 50-75% with monitoring. |
| Pediatric use | Oral loading: 10-20 mcg/kg in divided doses over 24 hours; maintenance: 5-10 mcg/kg once daily. IV loading: 10-15 mcg/kg; maintenance: 4-8 mcg/kg once daily. Monitor levels. |
| Geriatric use | Reduced dose: initial maintenance 0.0625-0.125 mg once daily due to age-related renal impairment and increased sensitivity. Monitor renal function and serum digoxin levels. |
| 1st trimester | Digoxin crosses the placenta. Use only if maternal benefit outweighs fetal risk, as fetal toxicity is possible. |
| 2nd trimester | Similar to t1; monitor maternal serum levels and fetal well-being. |
| 3rd trimester | Risk of fetal bradycardia and neonatal toxicity; therapeutic drug monitoring recommended. |
Clinical note
Comprehensive clinical and safety monograph for LANOXIN PEDIATRIC (LANOXIN PEDIATRIC).
| Placental transfer | Digoxin crosses the placenta readily, achieving fetal serum concentrations similar to maternal. Transfer is via passive diffusion. |
| Breastfeeding | Digoxin is excreted into breast milk in low concentrations (milk:plasma ratio ~0.59). The amount ingested by the infant is subtherapeutic and generally not expected to cause adverse effects. Caution is advised in neonates with renal impairment. |
■ FDA Black Box Warning
Digitalis toxicity can cause severe arrhythmias; monitoring of serum digoxin levels required.
| Common Effects | Visual impairment Skin rash Nausea Vomiting Diarrhea Dizziness Arrhythmia irregular heartbeats |
| Serious Effects |
Hypersensitivity to digoxin or any component of the formulationVentricular fibrillationWolff-Parkinson-White syndrome with atrial fibrillation or flutter (unless protected by an accessory pathway ablation)
| Precautions | Risk of toxicity in renal impairment, electrolyte disturbances, and drug interactions; monitor digoxin levels and ECG. |
| Food/Dietary | Avoid concurrent ingestion of high-fiber foods, as they may reduce absorption. Separate dosing by at least 2 hours from meals rich in bran, oats, or other fiber. Maintain consistent dietary potassium intake; both low and high potassium can affect digoxin toxicity. Grapefruit juice may increase absorption; avoid excessive consumption. |
Loading safety data…
| Lactation Rating | L2 (Limited data - probably compatible) |
| Teratogenic Risk | First trimester: No evidence of increased risk of major malformations. Second/third trimester: Potential for fetal bradycardia, cardiac arrhythmias, and intrauterine growth restriction due to transplacental transfer and maternal hemodynamic changes. |
| Fetal Monitoring | Monitor maternal serum digoxin levels, renal function, electrolytes (especially potassium, magnesium, calcium), and ECG for signs of toxicity. Assess fetal heart rate and rhythm via ultrasound or non-stress test, as well as fetal growth and amniotic fluid volume. |
| Fertility Effects | No known adverse effects on fertility from digoxin. Underlying cardiac disease may impact pregnancy outcomes. |
| Clinical Pearls | Lanoxin Pediatric (digoxin) requires monitoring of renal function and serum electrolytes (especially potassium and magnesium) due to narrow therapeutic index. Check digoxin levels 6-8 hours after dose; therapeutic range 0.8-2.0 ng/mL. Avoid concurrent use with drugs that affect renal function or electrolyte balance. |
| Patient Advice | Take exactly as prescribed at the same time each day. Do not double the dose if you miss one. · Do not stop taking without consulting your doctor. Sudden withdrawal may worsen heart condition. · Watch for signs of toxicity: nausea, vomiting, diarrhea, vision changes (blurring, yellow-green halos), confusion, irregular heartbeat. · Keep all appointments for blood tests to monitor levels and kidney function. · Contact your doctor before taking any new medications, including over-the-counter drugs and supplements. · Limit alcohol and avoid potassium-sparing diuretics unless prescribed. Maintain consistent dietary intake of potassium-rich foods. |