Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
CINACALCET HYDROCHLORIDE vs DIGOXIN PEDIATRIC
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Allosteric activator of the calcium-sensing receptor (Ca SR) on parathyroid chief cells, increasing sensitivity to extracellular calcium and reducing parathyroid hormone (PTH) secretion.
Inhibits sodium-potassium ATPase, increasing intracellular sodium, which promotes calcium influx via sodium-calcium exchanger, enhancing cardiac contractility. Also increases vagal tone, slowing AV conduction.
Secondary hyperparathyroidism in patients with chronic kidney disease on dialysis,Hypercalcemia in patients with parathyroid carcinoma,Severe hypercalcemia in patients with primary hyperparathyroidism who are unable to undergo parathyroidectomy
Heart failure (FDA-approved for pediatric patients with heart failure),Atrial fibrillation (off-label for rate control in pediatric patients)
30 mg orally once daily, titrate every 2-4 weeks to a maximum of 180 mg once daily to achieve target intact parathyroid hormone (i PTH) level.
For pediatric patients, digoxin pediatric dosing is weight-based; no standard adult dose. Typical pediatric loading dose: 10-12 mcg/kg orally divided every 6-8 hours, with maintenance: 5-10 mcg/kg/day divided every 12 hours. For infants <1 month, loading: 10-15 mcg/kg, maintenance: 4-6 mcg/kg/day. For children 1-24 months, loading: 15-20 mcg/kg, maintenance: 5-8 mcg/kg/day. For children >2 years, loading: 10-15 mcg/kg, maintenance: 3-5 mcg/kg/day.
Terminal elimination half-life: 30–40 hours in patients with normal renal function; prolonged to 42–83 hours in moderate to severe hepatic impairment. Steady-state reached within 7 days.
Terminal elimination half-life in neonates is 35-70 hours, infants 18-30 hours, children 12-30 hours, and adults 36-48 hours; prolonged in renal impairment and hypothyroidism.
Hepatic via CYP3A4, CYP2D6, and CYP1A2; major metabolites are inactive.
Primarily renally excreted unchanged; minimal hepatic metabolism (mostly via reduction, hydrolysis, and conjugation in older children).
Renal: 80% (as metabolites), Fecal: 15%, Biliary: negligible.
Renal excretion accounts for 50-70% of elimination as unchanged drug; biliary/fecal excretion accounts for 30-40%, primarily as metabolites; enterohepatic recirculation occurs.
97% bound to albumin.
25% bound to serum albumin; binding decreases in uremia and hyperbilirubinemia.
Approximately 1.7 L/kg (1000 L for 70 kg person), indicating extensive tissue distribution.
Vd: 6-10 L/kg in infants and children, 5-7 L/kg in adults; large Vd indicates extensive tissue binding, particularly to cardiac muscle (Na+/K+-ATPase).
76–82% (oral); food increases AUC by 50–80%.
Oral: 60-80% (elixir 70-85%, tablets 60-75%); IM: 70-85% (but erratic absorption and pain limit use); IV: 100%.
No dose adjustment required for any degree of renal impairment, including end-stage renal disease (ESRD) on dialysis.
Digoxin is primarily renally excreted. For pediatric patients, if GFR <30 m L/min/1.73m2, reduce maintenance dose by 50% and monitor serum levels. For GFR 30-60, reduce dose by 25-50%. In neonates with renal impairment, dose reduction proportional to creatinine clearance.
Mild hepatic impairment (Child-Pugh A): no dose adjustment. Moderate to severe hepatic impairment (Child-Pugh B or C): reduce starting dose to 30 mg daily and monitor i PTH and serum calcium closely.
Digoxin is minimally hepatically metabolized; no dose adjustment required for hepatic impairment. However, in Child-Pugh class C, monitor levels due to potential altered distribution.
Not established for pediatric patients; safety and efficacy in children have not been determined.
See standard_dosing. Weight-based dosing: total digitalizing dose (TDD) and maintenance as above. For premature infants, TDD 10-15 mcg/kg, maintenance 3-5 mcg/kg/day divided q12h. For full term neonates, TDD 15-20 mcg/kg, maintenance 5-7 mcg/kg/day. For infants 1-24 months, TDD 20-25 mcg/kg, maintenance 7-10 mcg/kg/day. For children 2-10 years, TDD 10-15 mcg/kg, maintenance 5-7 mcg/kg/day. For children >10 years, TDD 10-15 mcg/kg, maintenance 3-5 mcg/kg/day. Divide TDD into 3-4 doses every 6-8 hours. Maintenance started 12 hours after last loading dose.
No specific dose adjustment recommended; clinical studies included patients aged 65 and older, but no overall differences in safety or efficacy were observed. Use with caution due to potential for increased sensitivity.
Not applicable for pediatric formulation. For elderly, use adult digoxin dosing with caution: reduced renal function may require lower maintenance doses. Typical adult maintenance: 0.0625-0.25 mg daily based on renal function and lean body mass.
None.
Toxicity can be life-threatening. Use caution in renal impairment, electrolyte disturbances (hypokalemia, hypomagnesemia, hypercalcemia). Narrow therapeutic index requires monitoring.
Hypocalcemia: Can cause life-threatening hypocalcemia; monitor serum calcium levels frequently.,Seizures: Increased risk, especially in patients with history of seizure disorder.,QT interval prolongation: Hypocalcemia may exacerbate QT prolongation; monitor ECGs in patients with risk factors.,Hypotension and worsening heart failure: Cases reported, especially in patients with impaired cardiac function.,Adynamic bone disease: May develop with oversuppression of PTH; monitor bone-specific alkaline phosphatase.
Monitor serum digoxin levels, renal function, electrolytes (potassium, magnesium, calcium). Risk of arrhythmias (including ventricular fibrillation, bradycardia, AV block). Use with caution in patients with thyroid disease, acute myocardial infarction, or myocarditis.
Hypocalcemia,Known hypersensitivity to cinacalcet or any component of the formulation
Ventricular fibrillation, hypersensitivity to digitalis preparations, hypokalemia (uncorrected), hypercalcemia (uncorrected), AV block (second or third degree) unless pacemaker present.
Take with food or immediately after a dialysis treatment. Avoid high-calcium meals (e.g., dairy) within 2 hours of dosing as calcium binds cinacalcet and reduces absorption. No other dietary restrictions; maintain consistent calcium intake per renal diet.
High-fiber foods may decrease absorption; take digoxin 1 hour before or 2 hours after meals. Avoid natural licorice, which can cause hypokalemia and increase toxicity. Maintain consistent dietary potassium intake.
FDA Pregnancy Category C. No adequate studies in pregnant women. In animal studies, cinacalcet produced fetal toxicity (reduced fetal weight, increased incidence of skeletal variations) at doses 0.5-4 times the maximum human dose. Risk cannot be ruled out. Use only if potential benefit justifies potential risk to fetus.
Digoxin crosses the placenta. First trimester: No increased risk of major malformations reported in human studies. Second/third trimester: Potential for fetal toxicity (e.g., bradycardia, cardiac arrhythmias) at maternal toxic doses. No known teratogenicity at therapeutic doses.
No data on presence in human milk. In lactating rats, cinacalcet was excreted in milk with milk:plasma ratio approximately 2.4. Potential for serious adverse reactions in nursing infants; decision to discontinue nursing or drug should consider importance of drug to mother.
Digoxin is excreted into breast milk in low concentrations. M/P ratio approximately 0.6–0.9. Infant dose via milk is <1% of maternal weight-adjusted dose, unlikely to cause adverse effects in term infants. Caution in preterm or neonates with renal impairment.
No specific dosing adjustments are established due to lack of pharmacokinetic data in pregnancy. Serum calcium and PTH should be monitored frequently to guide dosing, as volume distribution and clearance may change. Generally, maintain lowest effective dose to control hyperparathyroidism.
During pregnancy, increased volume of distribution and renal clearance may reduce serum digoxin levels. Dose adjustments may be required based on therapeutic drug monitoring; typical dose increase of 20–30% in third trimester. Postpartum, reduce dose to prepregnancy level to avoid toxicity.
Monitor serum calcium within 1 week of initiation or dose adjustment; cinacalcet may cause hypocalcemia, so do not start if calcium <8.4 mg/d L. Correct elevated PTH in CKD patients with i PTH >300 pg/m L on dialysis; not for use in non-dialysis CKD. QTc prolongation risk: obtain baseline ECG and monitor electrolytes, especially if on QT-prolonging drugs. Nausea and vomiting are common; administer with food or after dialysis session to improve tolerance.
Monitor serum digoxin levels (therapeutic range 0.5-2 ng/m L) and renal function, especially in neonates. Correct hypokalemia, hypomagnesemia, and hypercalcemia before administration to reduce toxicity risk. Use with caution in patients with WPW, hypertrophic cardiomyopathy, or incomplete heart block. Dosing in infants and children is based on weight and renal function.
Take cinacalcet with food or right after a dialysis session to reduce stomach upset.,Do not stop taking this medication suddenly; consult your doctor if you have side effects.,Report symptoms of low calcium such as muscle cramps, numbness, or tingling in fingers/toes.,Tell your doctor if you have a history of seizures or liver problems.,Avoid taking strong CYP3A4 inhibitors (e.g., ketoconazole, erythromycin) unless prescribed; inform all healthcare providers.
Take exactly as prescribed; do not double up doses.,Monitor for signs of toxicity: nausea, vomiting, vision changes (yellow-green halos), arrhythmias.,Keep medication out of reach of children; immediate medical attention if overdose suspected.,Do not stop abruptly without consulting healthcare provider.,Inform healthcare provider of all medications, including OTC and herbal supplements.
"Cinacalcet, a potent CYP3A4 inhibitor, significantly decreases the metabolism of Indinavir, a CYP3A4 substrate. This leads to elevated plasma concentrations of Indinavir, increasing the risk of dose-related toxicities such as nephrolithiasis, acute interstitial nephritis, and hepatotoxicity. The interaction may require Indinavir dose reduction and close monitoring for adverse effects."
"Duloxetine, a moderate inhibitor of CYP2D6 and CYP1A2, can reduce the metabolism of cinacalcet, a CYP2D6 and CYP1A2 substrate, leading to increased plasma concentrations of cinacalcet. This elevation may enhance the pharmacodynamic effects of cinacalcet, including a greater reduction in parathyroid hormone (PTH) and increased risk of hypocalcemia. Clinically, patients may experience symptoms such as paresthesias, muscle cramps, or cardiac arrhythmias due to electrolyte disturbances."
"Nitrofural, an antibacterial agent, is a potent inhibitor of CYP450 enzymes, particularly CYP3A4 and CYP1A2. Cinacalcet is extensively metabolized by CYP3A4 and, to a lesser extent, CYP1A2. Concomitant use of Nitrofural with Cinacalcet significantly reduces the systemic clearance of Cinacalcet, leading to elevated plasma concentrations. This increases the risk of dose-dependent adverse effects such as hypocalcemia, QT prolongation, and seizures."
"Eflornithine, an ornithine decarboxylase inhibitor used in the treatment of African trypanosomiasis and hirsutism, may reduce the therapeutic efficacy of digoxin, a cardiotonic glycoside used for heart failure and atrial fibrillation. The proposed mechanism involves eflornithine-induced alterations in gastrointestinal motility or absorption, potentially decreasing digoxin bioavailability. This could lead to subtherapeutic digoxin levels, diminished inotropic and chronotropic effects, and increased risk of arrhythmias or worsening heart failure."
"Osimertinib, a tyrosine kinase inhibitor used in non-small cell lung cancer, can inhibit P-glycoprotein (P-gp) transport in the gastrointestinal tract and kidneys, leading to increased absorption and reduced renal clearance of digoxin. This elevation in serum digoxin concentration heightens the risk of digoxin toxicity, including cardiac arrhythmias (e.g., bradycardia, atrial tachycardia with block) and gastrointestinal symptoms such as nausea and vomiting. Clinical monitoring for digoxin toxicity is warranted, especially when initiating or adjusting osimertinib therapy."
"Lenvatinib, a tyrosine kinase inhibitor, may reduce the therapeutic efficacy of digoxin by interfering with its cardiotonic effects. This interaction could lead to decreased inotropic support in patients with heart failure, potentially worsening cardiac function and clinical outcomes. The clinical consequence is a possible loss of rate control in atrial fibrillation or diminished contractility in systolic dysfunction."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about CINACALCET HYDROCHLORIDE vs DIGOXIN PEDIATRIC, answered by our medical review team.
CINACALCET HYDROCHLORIDE is a Calcimimetic that works by Allosteric activator of the calcium-sensing receptor (Ca SR) on parathyroid chief cells, increasing sensitivity to extracellular calcium and reducing parathyroid hormone (PTH) secretion.. DIGOXIN PEDIATRIC is a Cardiac Glycoside that works by Inhibits sodium-potassium ATPase, increasing intracellular sodium, which promotes calcium influx via sodium-calcium exchanger, enhancing cardiac contractility. Also increases vagal tone, slowing AV conduction.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between CINACALCET HYDROCHLORIDE and DIGOXIN PEDIATRIC depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of CINACALCET HYDROCHLORIDE is: 30 mg orally once daily, titrate every 2-4 weeks to a maximum of 180 mg once daily to achieve target intact parathyroid hormone (i PTH) level.. The standard adult dose of DIGOXIN PEDIATRIC is: For pediatric patients, digoxin pediatric dosing is weight-based; no standard adult dose. Typical pediatric loading dose: 10-12 mcg/kg orally divided every 6-8 hours, with maintenance: 5-10 mcg/kg/day divided every 12 hours. For infants <1 month, loading: 10-15 mcg/kg, maintenance: 4-6 mcg/kg/day. For children 1-24 months, loading: 15-20 mcg/kg, maintenance: 5-8 mcg/kg/day. For children >2 years, loading: 10-15 mcg/kg, maintenance: 3-5 mcg/kg/day.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between CINACALCET HYDROCHLORIDE and DIGOXIN PEDIATRIC in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. CINACALCET HYDROCHLORIDE is classified as Category C. FDA Pregnancy Category C. No adequate studies in pregnant women. In animal studies, cinacalcet produced fetal toxicity (reduced fetal weight, increased incidence of skeletal variat. DIGOXIN PEDIATRIC is classified as Category A/B. Digoxin crosses the placenta. First trimester: No increased risk of major malformations reported in human studies. Second/third trimester: Potential for fetal toxicity (e.g., brady. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.