Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
CALCIUM DISODIUM VERSENATE vs CHEMET
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Calcium disodium edetate chelates heavy metals (e.g., lead, cadmium) forming stable, water-soluble complexes that are excreted renally, reducing metal burden and toxicity.
Chelates heavy metals, particularly lead, mercury, and arsenic, by forming soluble complexes that are excreted renally. Acts as an antidote by binding to toxic metals and reducing their tissue concentrations.
Treatment of lead poisoning (including symptomatic and asymptomatic patients with blood lead levels ≥45 μg/d L in children and ≥70 μg/d L in adults),Off-label: treatment of other heavy metal toxicities (e.g., cadmium, chromium, manganese, nickel)
Treatment of acute and chronic lead poisoning,Treatment of mercury poisoning,Treatment of arsenic poisoning,Diagnostic chelation challenge test
1-2 g intramuscularly or intravenously every 12 hours for 3-5 days, followed by 2-5 days off, repeating as needed.
10-20 mg/kg orally every 8 hours for 5 days; maximum single dose 1250 mg.
Terminal elimination half-life: 20-30 minutes for unchelated drug; lead-chelate complex half-life: 1-2 hours. Clinical context: Short half-life necessitates continuous or repeated dosing for sustained chelation.
Terminal elimination half-life: 1.6–3.5 hours (mean 2.1 h) in adults with normal renal function; prolonged in renal impairment (up to 20 h).
Not metabolized; excreted unchanged in urine via glomerular filtration and tubular secretion.
Metabolized in liver to disulfide dimers; undergoes enterohepatic circulation; primarily excreted renally as metabolites and unchanged drug.
Renal: >95% as chelated lead complex; biliary/fecal: negligible (<5%)
Renal: 80–90% as unchanged drug and metabolites (primarily as chelated complexes); biliary/fecal: <10%.
<5% bound to plasma proteins (albumin)
Approximately 80% bound to plasma proteins, primarily albumin.
0.2-0.3 L/kg; primarily distributes to extracellular fluid, minimal intracellular penetration
0.5–0.8 L/kg, indicating distribution mainly in extracellular fluid; limited intracellular penetration.
IV: 100%; IM: approximately 80-90% (due to local chelation and partial excretion)
20–40% after oral administration due to first-pass metabolism and limited absorption.
GFR > 50 m L/min: no adjustment; GFR 10-50 m L/min: administer 50% of usual dose; GFR < 10 m L/min: administer 25% of usual dose or consider alternative therapy.
GFR 50-80 m L/min: same dose every 12 hours. GFR 10-49 m L/min: same dose every 24 hours. GFR <10 m L/min: same dose every 48 hours.
No specific guidelines available; use with caution and monitor liver function in severe hepatic impairment (Child-Pugh C).
No specific recommendations; caution in severe hepatic impairment (Child-Pugh C) due to potential toxicity.
25 mg/kg/dose intramuscularly or intravenously every 12 hours for 3-5 days; maximum 1 g/dose.
Children >1 year: 10-20 mg/kg/dose orally every 8 hours for 5 days; maximum 1250 mg/dose.
Consider renal function; elderly patients often require dose reduction based on creatinine clearance; start at lower end of dosing range and monitor for adverse effects.
Consider starting at lower end of dosing range (10 mg/kg) due to potential renal impairment; adjust per renal function.
This drug is not indicated for the treatment of iron deficiency anemia or hemochromatosis. Do not use in patients with severe renal impairment. Prolonged or excessive use may lead to toxicities including renal failure, convulsions, and cardiac arrhythmias.
None
Renal toxicity: monitor renal function and urine output; avoid excessive doses. Neurotoxicity: can cause tremors, seizures, and encephalopathy, especially with high doses or rapid infusion. Hydration: maintain adequate hydration to promote urinary excretion. Rebound metal mobilization: may transiently increase tissue metal levels. Hypocalcemia: due to calcium displacement; monitor serum calcium. Cardiac effects: risk of arrhythmias, especially with rapid IV administration.
May cause nephrotoxicity; monitor renal function,May cause hypersensitivity reactions, including fever, rash, and anaphylaxis,Monitor for neutropenia; obtain CBC before and during therapy,Use caution in patients with hepatic impairment or glucose-6-phosphate dehydrogenase (G6PD) deficiency,May chelate essential minerals (e.g., zinc, copper); monitor levels with prolonged use,Not recommended for routine use in asymptomatic lead poisoning with low blood lead levels
Absolute: anuria or severe renal failure (creatinine clearance <20 m L/min). Relative: hypersensitivity to edetate salts, pre-existing renal disease, concurrent use with other nephrotoxic drugs.
Hypersensitivity to dimercaprol or any component of the formulation,Hepatic failure (except severe heavy metal poisoning),Concurrent use with iron (increases nephrotoxicity); avoid iron therapy within 24 hours,Pregnancy (if not life-saving indication due to risk of teratogenicity),Peanut allergy (formulation contains peanut oil)
Avoid excessive intake of calcium and vitamin D supplements during therapy (may reduce chelation efficacy). Maintain adequate hydration with water. No specific food restrictions, but a balanced diet is recommended to prevent deficiencies of essential minerals (zinc, copper) that may be chelated.
No specific food interactions reported. However, due to gastrointestinal side effects (nausea, vomiting), it is advisable to maintain small, frequent meals. Avoid alcohol.
Limited human data. Animal studies show fetal toxicity at high doses. First trimester: theoretical risk of chelation of essential minerals. Second and third trimesters: risk of fetal zinc/corper deficiency if prolonged use. Avoid unless maternal benefit outweighs risk.
FDA Pregnancy Category C. First trimester: No adequate studies, but animal studies show fetal resorption at maternally toxic doses, risk cannot be excluded. Second and third trimesters: No specific teratogenicity, but may cause anemia in fetus due to maternal chelation of essential metals. Avoid use unless clearly needed.
Excreted into breast milk in low amounts; M/P ratio unknown. Caution due to potential for infant mineral chelation. Use only if clearly needed.
No human data on excretion in breast milk. M/P ratio unknown. Caution due to potential for infant exposure and chelation of trace elements; consider benefit-risk. Avoid breastfeeding during therapy and for 2 weeks after last dose.
No specific dose adjustment required; however, monitor for hypocalcemia and mineral depletion. Increased risk of renal toxicity in pregnancy; ensure adequate hydration.
No specific dose adjustments recommended for pregnancy. Increased plasma volume in pregnancy may alter pharmacokinetics, but studies not performed. Use lowest effective dose; monitor therapeutic response and toxicity closely.
Administer deep IM or slow IV infusion (over 2-4 hours) to avoid thrombophlebitis. Monitor urine output and renal function; nephrotoxicity is dose-dependent. Discontinue if oliguria or rising creatinine occurs. For lead encephalopathy, give concurrently with BAL (dimercaprol) to redistribute lead from CNS to blood. Use with caution in patients with pre-existing renal disease, hepatitis, or history of allergic reactions. EDTA can chelate essential metals (zinc, copper) leading to deficiencies during prolonged therapy.
Chelation therapy with dimercaprol (CHEMET) should be initiated within 4 hours of arsenic or mercury exposure for maximal efficacy. Administer only via deep intramuscular injection, never intravenously. Monitor renal function and urine output closely, as dimercaprol can cause nephrotoxicity. Alkalinize urine to p H 7.5-8.5 to decrease renal precipitation of metal-drug complexes. Use with caution in patients with glucose-6-phosphate dehydrogenase deficiency due to risk of hemolysis. Contraindicated in patients with peanut allergy (vehicle is peanut oil).
Report any signs of allergic reaction (rash, itching, difficulty breathing) or injection site pain/swelling immediately.,Drink plenty of fluids (unless instructed otherwise) to help flush out lead through urine.,Avoid taking any other medications, supplements, or over-the-counter products without consulting your doctor, as they may affect treatment.,Do not miss scheduled blood and urine tests; they are essential to monitor lead levels and kidney function.,Severe lead poisoning may cause fatigue, headache, abdominal pain; report these symptoms if they worsen.
This medication is given as a shot into a muscle, usually in the buttock. It may cause pain at the injection site.,You may experience a metallic taste, nausea, vomiting, headache, or burning sensation in the mouth or throat.,Drink plenty of fluids unless otherwise instructed to help flush metals from your body.,Avoid alcohol during treatment and for at least 48 hours after the last dose.,Report any signs of allergic reaction (rash, itching, difficulty breathing) or dark urine immediately.
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about CALCIUM DISODIUM VERSENATE vs CHEMET, answered by our medical review team.
CALCIUM DISODIUM VERSENATE is a Chelating Agent that works by Calcium disodium edetate chelates heavy metals (e.g., lead, cadmium) forming stable, water-soluble complexes that are excreted renally, reducing metal burden and toxicity.. CHEMET is a Chelating agent that works by Chelates heavy metals, particularly lead, mercury, and arsenic, by forming soluble complexes that are excreted renally. Acts as an antidote by binding to toxic metals and reducing their tissue concentrations.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between CALCIUM DISODIUM VERSENATE and CHEMET 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 CALCIUM DISODIUM VERSENATE is: 1-2 g intramuscularly or intravenously every 12 hours for 3-5 days, followed by 2-5 days off, repeating as needed.. The standard adult dose of CHEMET is: 10-20 mg/kg orally every 8 hours for 5 days; maximum single dose 1250 mg.. 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 CALCIUM DISODIUM VERSENATE and CHEMET 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. CALCIUM DISODIUM VERSENATE is classified as Category C. Limited human data. Animal studies show fetal toxicity at high doses. First trimester: theoretical risk of chelation of essential minerals. Second and third trimesters: risk of fet. CHEMET is classified as Category C. FDA Pregnancy Category C. First trimester: No adequate studies, but animal studies show fetal resorption at maternally toxic doses, risk cannot be excluded. Second and third trimes. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.