Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
CHEMET vs CUPRIMINE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
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.
Chelates copper, forming a stable complex that is excreted renally, reducing systemic copper accumulation.
Treatment of acute and chronic lead poisoning,Treatment of mercury poisoning,Treatment of arsenic poisoning,Diagnostic chelation challenge test
Wilson disease,Cystinuria,Rheumatoid arthritis (off-label)
10-20 mg/kg orally every 8 hours for 5 days; maximum single dose 1250 mg.
250-500 mg orally 4 times daily, titrated to maintain urinary copper excretion >2 mg/day. Maximum: 2 g/day.
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).
Terminal half-life: 4–6 hours. Clinical context: After discontinuation, urinary copper excretion declines within 2–3 hours but may persist for several days due to tissue redistribution.
Metabolized in liver to disulfide dimers; undergoes enterohepatic circulation; primarily excreted renally as metabolites and unchanged drug.
Metabolized by oxidation and reduction; primarily renal elimination.
Renal: 80–90% as unchanged drug and metabolites (primarily as chelated complexes); biliary/fecal: <10%.
Renal: ~80% as unchanged drug, biliary/fecal: <5%
Approximately 80% bound to plasma proteins, primarily albumin.
~70% bound, primarily to serum albumin.
0.5–0.8 L/kg, indicating distribution mainly in extracellular fluid; limited intracellular penetration.
Vd: 0.5–1.0 L/kg (approximately 70 L in adults). Indicates distribution into total body water with moderate tissue binding.
20–40% after oral administration due to first-pass metabolism and limited absorption.
Oral: Approximately 40–70% (variable, reduced by food, especially high-protein meals; administration on empty stomach recommended).
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.
Contraindicated in severe renal impairment (GFR <30 m L/min). For GFR 30-60 m L/min: reduce dose by 25-50%. Monitor urinary copper and adjust accordingly.
No specific recommendations; caution in severe hepatic impairment (Child-Pugh C) due to potential toxicity.
No specific adjustment for Child-Pugh class A or B; use with caution in severe hepatic impairment (Child-Pugh C) due to hepatotoxicity risk. Monitor liver function.
Children >1 year: 10-20 mg/kg/dose orally every 8 hours for 5 days; maximum 1250 mg/dose.
10-20 mg/kg/day orally divided into 2-4 doses; typical starting dose 15 mg/kg/day for Wilson disease (max 1 g/day). Titrate based on urinary copper.
Consider starting at lower end of dosing range (10 mg/kg) due to potential renal impairment; adjust per renal function.
Start at lower end of dosing range (250 mg twice daily) due to age-related renal decline; monitor renal function and copper levels.
None
WARNING: CUPRIMINE can cause severe bone marrow depression leading to aplastic anemia, leukopenia, thrombocytopenia, and agranulocytosis. Deaths have occurred. Monitor blood counts closely.
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
Bone marrow suppression, renal toxicity (proteinuria, hematuria), lupus-like syndrome, myasthenia gravis-like syndrome, rash, and hypersensitivity reactions. Monitor renal function, blood counts, and urinalysis regularly.
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)
History of penicillamine-related aplastic anemia or agranulocytosis; concurrent gold therapy, antimalarial drugs, or immunosuppressants; rheumatoid arthritis patients with renal insufficiency.
No specific food interactions reported. However, due to gastrointestinal side effects (nausea, vomiting), it is advisable to maintain small, frequent meals. Avoid alcohol.
Take on an empty stomach. Avoid food, especially milk, and any mineral supplements (iron, zinc, calcium) for at least 1 hour before and 2 hours after dosing, as they reduce absorption. Alcohol should be avoided due to potential hepatotoxicity.
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.
First trimester: High risk of congenital anomalies including cutis laxa, micrognathia, limb deformities, and CNS defects. Second trimester: Continued risk of fetal harm, potential for growth restriction. Third trimester: Risk of fetal copper deficiency and associated neurological impairment. Pregnancy category D.
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.
Excreted in breast milk. M/P ratio not established. Contraindicated in breastfeeding due to potential for severe adverse effects (hypersensitivity, bone marrow suppression) in the infant.
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.
No standard dose adjustment recommended; use lowest effective dose. Monitor serum copper to maintain therapeutic levels due to altered pharmacokinetics in pregnancy (increased volume of distribution, renal clearance).
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).
Monitor for proteinuria and hematuria; perform urinalysis weekly initially, then monthly. Penicillamine can cause bone marrow suppression; obtain baseline CBC and differential, then monitor every 2 weeks for first 6 months, then monthly. Drug-induced lupus and myasthenia gravis are rare but serious autoimmune adverse effects. Avoid in patients with a history of penicillin allergy due to potential cross-sensitivity. Administer on an empty stomach at least 1 hour before or 2 hours after meals to enhance absorption. Dose adjustments needed in renal impairment. Pyridoxine (vitamin B6) supplementation (25-50 mg/day) is recommended to prevent deficiency caused by penicillamine. For Wilson disease, monitor 24-hour urinary copper excretion to guide therapy.
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.
Take this medication on an empty stomach, at least 1 hour before or 2 hours after meals.,Do not skip doses; take exactly as prescribed and do not double up if a dose is missed.,Report any signs of allergy promptly: rash, itching, fever, joint pain, or swollen lymph nodes.,Contact your doctor immediately if you experience easy bruising, bleeding, or signs of infection such as fever or sore throat.,Inform your doctor about any planned vaccinations; avoid live vaccines while on this medication.,You may need regular blood and urine tests to monitor for side effects.,If you are taking iron supplements or other mineral supplements, take them at least 2 hours apart from this medication to prevent reduced absorption.,Use effective contraception if you are of childbearing age; this drug can harm an unborn baby.,Avoid alcohol as it may increase the risk of liver toxicity.,Notify your dentist about your medication history before any dental procedures.
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 CHEMET vs CUPRIMINE, answered by our medical review team.
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.. CUPRIMINE is a Chelating Agent that works by Chelates copper, forming a stable complex that is excreted renally, reducing systemic copper accumulation.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between CHEMET and CUPRIMINE 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 CHEMET is: 10-20 mg/kg orally every 8 hours for 5 days; maximum single dose 1250 mg.. The standard adult dose of CUPRIMINE is: 250-500 mg orally 4 times daily, titrated to maintain urinary copper excretion >2 mg/day. Maximum: 2 g/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 CHEMET and CUPRIMINE 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. 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. CUPRIMINE is classified as Category C. First trimester: High risk of congenital anomalies including cutis laxa, micrognathia, limb deformities, and CNS defects. Second trimester: Continued risk of fetal harm, potential . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.