Succimer

Succimer is a lead chelator; it forms water soluble chelates and, consequently, increases the urinary excretion of lead.

• CHEMET is indicated for the treatment of lead poisoning in pediatric patients aged 1 year and older with blood lead levels above 45 mcg/dL. CHEMET is a lead chelator indicated for the treatment of lead poisoning in pediatric patients aged 1 year and older with blood lead levels above 45 mcg/dL.

• CHEMET is contraindicated in patients with a history of hypersensitivity reaction to succimer. Reactions have included mucocutaneous vesicular eruptions, urticaria, and angioedema [see Warnings and Precautions (5.1) ] .contraindicated

See Full Prescribing Information for important pretreatment evaluations. ( 2.1 ) Ensure patients receiving CHEMET are adequately hydrated. ( 2.3 ) Administer CHEMET capsules whole when possible. ( 2.3 ) Pediatric patients who cannot swallow whole capsules: Sprinkle contents of capsule in food (or on a spoon followed by a drink). ( 2.3 ) Recommended Dosage: 10 mg/kg or 350 mg/m 2 orally every 8 hours for five days followed by 10 mg/kg or 350 mg/m 2 orally every 12 hours for an additional 14 days. ( 2.2 ) 2.1 Important Pretreatment Evaluations Identify the source of lead in the pediatric patient's environment and eliminate the source prior to beginning treatment with CHEMET. Assess the following before initiating treatment with CHEMET: Blood lead concentration Complete blood count (CBC) with differential and platelets [see Dosage and Administration (2.2) , Warnings and Precautions (5.2) ] Ensure absolute neutrophil count (ANC) > 1500/mcL [see Dosage and Administration (2.2) ] Transaminases (AST/ALT) [see Warnings and Precautions (5.3) and Use in Specific Populations (8.6) ] Renal function with blood urea nitrogen (BUN), creatinine, urinary protein [see Use in Specific Populations (8.5) ] . Patients who have previously received Edetate calcium disodium (CaNa 2 EDTA) with or without dimercaprol may receive CHEMET for subsequent treatment after an interval of four weeks.

Hypersensitivity and dermatologic reactions: Interrupt treatment if rash or mucocutaneous vesicular eruptions occur. ( 5.1 ) Neutropenia: Monitor complete blood counts, interrupt treatment for ANC below 1200/mcL, and monitor for infection. ( 5.2 ) Hepatic Toxicity: Monitor hepatic transaminases (ALT/AST); interrupt treatment if above 5 times ULN. ( 5.3 ) Embryo-Fetal Toxicity: May cause fetal harm when administered to a pregnant woman. ( 5.5 ) 5.1 Hypersensitivity and Dermatologic Reactions CHEMET can cause hypersensitivity reactions and dermatologic reactions. Rash Rash occurs in approximately 4% of patients treated with CHEMET. Interrupt treatment if rash occurs. Consider rechallenge if lead levels are high enough to warrant retreatment. Hypersensitivity reactions including urticaria and angioedema have been reported on repeated administration of CHEMET [see Contraindications (4) ]. Mucocutaneous Reactions Mucocutaneous vesicular eruptions can occur with CHEMET use and may increase with each treatment course. Monitor patients requiring repeated CHEMET courses for the occurrence of mucocutaneous eruptions, including oral, urethral, and perianal. Interrupt treatment if mucocutaneous vesicular eruptions occur. 5.2 Neutropenia Iron chelators, including CHEMET, can cause neutropenia. Monitoring of complete blood counts is recommended [see Dosage and Administration (2.2) ] . Interrupt treatment if absolute neutrophil count (ANC) is <1200/mcL and interrupt treatment until recovery to above 1500/mcL (or the patient's baseline count).

The following clinically significant adverse reactions are described elsewhere in the labeling: Hypersensitivity and Dermatologic Reactions [see Warnings and Precautions (5.1) ] Neutropenia [see Warnings and Precautions (5.2) ] Hepatic Toxicity [see Warnings and Precautions (5.3) ] Most common adverse reactions (incidence ≥ 10%) in Pediatric patients: Digestive (nausea, vomiting, diarrhea, appetite loss, hemorrhoidal symptoms, metallic taste in mouth). ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Recordati Rare Diseases Inc. at 1-888-575-8344 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Table 2 presents the adverse reactions associated with Chemet in pediatric patients. Table 2 Incidence of Adverse Reactions Associated with Chemet in Pediatric Patients Body System: Adverse Reactions Pediatric Patients (n=191) Digestive Nausea, vomiting, diarrhea, appetite loss, hemorrhoidal symptoms, metallic taste in mouth 12% Body as a Whole Back pain, abdominal cramps, stomach pains, head pain, rib pain, chills, flank pain, fever, flu-like symptoms, heavy head/tired, head cold, headache, moniliasis. 5% Metabolic Elevated ALT or AST, alkaline phosphatase, serum cholesterol. 4% Respiratory Sore throat, rhinorrhea, nasal congestion, cough.

Pregnancy: May cause fetal harm. ( 8.1 ) Renal Impairment: Assess renal function. ( 8.6 ) Hepatic Impairment: Assess hepatic function. (8.7) 8.1 Pregnancy Risk Summary There are no studies with the use of CHEMET in pregnant women to inform drug-associated risks. Administration of CHEMET to pregnant mice during organogenesis at dose exposure of 11-times the human exposure at the maximum recommended human dose (MRHD) of 700 mg based on body surface area (BSA) resulted in maternal toxicity and mortality and impaired reflex development in offspring (see Animal Data ) . There are adverse effects on maternal and fetal outcomes associated with lead poisoning in pregnancy (see Clinical Considerations ) . CHEMET should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. The estimated background risk of major birth defects and miscarriage for the indicated population(s) is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. However, the background risk in the U.S general population of major birth defects is 2 to 4% and of miscarriage is 15 to 20% of clinically recognized pregnancies. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk Lead exposure in pregnancy may increase the risk of gestational hypertension.

Metabolism

Absorption Succimer achieved peak plasma concentrations at 1–2 hours. Elimination Metabolism Approximately 90% of absorbed dose is metabolized to mixed succimer-cysteine disulfides.

Doses of 2300 mg/kg in the rat and 2400 mg/kg in the mouse produced ataxia, convulsions, labored respiration and frequently death. Limited data indicate that CHEMET is dialyzable. In case of acute overdosage, consider use of induction of vomiting or gastric lavage followed by administration of an activated charcoal slurry and appropriate supportive therapy.

• Jan 30, 1991NDANDA019998Recordati Rare
• Feb 18, 2022NDANDA214993Theragnostics

1. 1Off Label Use2333%
2. 2Product Availability Issue913%
3. 3Arthralgia710%
4. 4Dizziness57.2%
5. 5Hypertension57.2%
6. 6No Adverse Event57.2%
7. 7Weight Increased57.2%
8. 8Asthenia45.8%
9. 9Condition Aggravated45.8%
10. 10Fatigue45.8%
11. 11Pain In Extremity45.8%
12. 12Skin Striae45.8%
13. 13Abdominal Pain Upper34.3%
14. 14Aortic Arteriosclerosis34.3%
15. 15Arrhythmia34.3%

Recent PubMed references pinned to Succimer as a MeSH major topic. Citations link to pubmed.ncbi.nlm.nih.gov.

• Oxidative stress induced by DMSA-IONPs impairs breast cancer cell migration and paracrine cell communication.
  Journal of nanobiotechnology · 2026 · Daviu N, Graciano-Casero C, Barber DF, et al.
  PMID 41957669DOI 10.1186/s12951-026-04412-3
• Acute Copper Toxicity: Succimer Makes you Less Blue.
  Journal of medical toxicology : official journal of the American College of Medical Toxicology · 2026 · Ivanov I, Abouelela W, Debbie T, et al.
  PMID 41770515DOI 10.1007/s13181-026-01117-9
• Antifungal repurposing of clinical chelator DMSA against Cryptococcus neoformans via laccase and histidine biosynthesis inhibition.
  Microbial pathogenesis · 2026 · Zhang C, Peng M, Hu Q, et al.
  PMID 41679612DOI 10.1016/j.micpath.2026.108375
• Role of 99m Tc-pentavalent dimercaptosuccinic acid brain single-photon emission computed tomography/computed tomography in evaluating treated adult glioma in the era of isocitrate dehydrogenase mutation status.
  Nuclear medicine communications · 2026 · Mostafa NM, Elsaady R, Mekawi M, et al.
  PMID 41668398DOI 10.1097/MNM.0000000000002120
• Clinical Significance and Prognosis of Renal Fusion Anomalies Detected by Tc-99m Dimercaptosuccinic Acid Scintigraphy.
  Clinical pediatrics · 2026 · Esen Agar B, Gurgoze MK, Kara A, et al.
  PMID 41618098DOI 10.1177/00099228261416161
• A data-driven respiratory motion correction for pediatric DMSA renal SPECT imaging: A simulation study.
  Medical physics · 2026 · Pijanowski J, Pretorius PH, Segars WP, et al.
  PMID 41532399DOI 10.1002/mp.70279
• Modified Top-Down Approach to Reduce Voiding Cystourethrograms: Diagnostic Accuracy of Late DMSA Scintigraphy and Renal Ultrasound for Predicting Vesicoureteral Reflux in Children > 2 Years. A Retrospective Audit.
  Indian pediatrics · 2026 · Babu R, Heera T, Sangeetha G, et al.
  PMID 41511707DOI 10.1007/s13312-025-00254-8
• Compounding of DMSA Radiopharmaceutical Kits During a Shortage.
  International journal of pharmaceutical compounding · 2025 · Galbraith W, Baumgartner M, Talley K, et al.
  PMID 41401042

The 9 most recently updated of 9 ClinicalTrials.gov registrations naming Succimer as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

• Monitoring, Detoxifying, and Rebalancing Metals During Acute Myeloid Leukemia (AML) Therapy, a Phase 2 Randomized Study
  Recruiting · Phase 2 · Interventional · 140 enrolled · M.D. Anderson Cancer Center
  NCT06811233updated 2026-04-23
• Edetate Calcium Disodium or Succimer in Treating Patients With Acute Myeloid Leukemia or Myelodysplastic Syndrome Undergoing Chemotherapy
  Recruiting · Phase 1 · Interventional · 58 enrolled · M.D. Anderson Cancer Center
  NCT03630991updated 2026-03-02
• Electrophysiological Study of the Functioning of Magnocellular Visual Pathway in Regular Cannabis Users
  Completed · Interventional · 163 enrolled · Central Hospital, Nancy, France
  NCT02864680updated 2021-04-29
• The Individual Therapy for Patients With Wilson's Disease
  Unknown · Early phase 1 · Interventional · 400 enrolled · Second Affiliated Hospital, School of Medicine, Zhejiang University
  NCT03957720updated 2019-05-21
• Treatment of Lead-Exposed Children Trial
  Completed · Phase 3 · Interventional · 780 enrolled · National Institute of Environmental Health Sciences (NIEHS)
  NCT00342849updated 2018-04-05
• Mercury Chelation to Treat Autism
  Withdrawn · Phase 2 · Interventional · 0 enrolled · National Institute of Mental Health (NIMH)
  NCT00376194updated 2013-09-18
• Dimercaptosuccinic Acid (DMSA) Treatment of Children With Autism and Heavy Metal Toxicity
  Completed · Phase 1 · Phase 2 · Interventional · 80 enrolled · Southwest College of Naturopathic Medicine
  NCT00811083updated 2008-12-18
• The Combined Effect of 2,3-Dimercaptosuccinic Acid and Multi-Nutrients on Children in Lead Poisoning
  Completed · Observational · 500 enrolled · China Medical University, China
  NCT00374894updated 2006-09-12
• Randomized Study of Succimer (Dimercaptosuccinic Acid) on Growth of Lead-Poisoned Children
  Completed · Interventional · 175 enrolled · Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
  NCT00004838updated 2005-06-24

Frequently asked questions

How does Succimer work?

Succimer is a lead chelator; it forms water soluble chelates and, consequently, increases the urinary excretion of lead.

What is Succimer used for?

According to FDA labeling, Succimer carries indications including: CHEMET is indicated for the treatment of lead poisoning in pediatric patients aged 1 year and older with blood lead levels above 45 mcg/dL. CHEMET is a lead chelator indicated for the treatment of lead poisoning in pediatric patients aged 1 year and older with blood lead levels above 45 mcg/dL.. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.

What class of drug is Succimer?

Succimer is classified as Lead Chelator, Lead Chelating Activity, Unknown Physiological Effect.

What are the brand names for Succimer?

Succimer is marketed under brand names including Chemet.

What are the contraindications for Succimer?

Succimer labeling lists contraindications including: CHEMET is contraindicated in patients with a history of hypersensitivity reaction to succimer. Reactions have included mucocutaneous vesicular eruptions, urticaria, and angioedema [see Warnings and Precautions (5.1) ] .. Always consult the full prescribing information and a clinician.