Succimer

Brand Names: Chemet

Drug Class: Lead Chelator

Overview

11 DESCRIPTION CHEMET (succimer) is an orally active, lead chelating agent. The chemical name for succimer is meso 2, 3-dimercaptosuccinic acid (DMSA). Its empirical formula is C 4 H 6 O 4 S 2 and molecular weight is 182.2. The meso -structural formula is: Succimer is a white crystalline powder with an unpleasant, characteristic mercaptan odor and taste.

Mechanism of Action

12 CLINICAL PHARMACOLOGY 12.1 Mechanism of Action Succimer is a lead chelator; it forms water soluble chelates and, consequently, increases the urinary excretion of lead. 12.2 Pharmacodynamics Effect on Essential Minerals In dose ranging studies performed in 18 men with blood lead levels of 44-96 mcg/dL, three groups of 6 patients received either 10, 6.7 or 3.3 mg/kg succimer orally every 8 hours for 5 days. After five days the mean blood lead levels of the three groups decreased 72.5%, 58.3% and 35.5% respectively. The mean urinary lead excretions in the initial 24 hours were 28.6, 18.6 and 12.3 times the pretreatment 24 hour urinary lead excretion. CHEMET had no significant effect on the urinary elimination of iron, calcium or magnesium. Zinc excretion doubled during treatment. 12.

Indications

  • 1 INDICATIONS AND USAGE 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. ( 1 ) Limitations of Use CHEMET is not indicated for prophylaxis of lead poisoning in a lead-containing environment. ( 1 ) CHEMET does not cross the blood-brain barrier and is not indicated to treat encephalopathy associated with lead toxicity.

Common Doses

  • 10 mg
  • 350 mg
  • 100 mg
  • 200 mg

Dosage

2 DOSAGE AND ADMINISTRATION 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.

Contraindications

  • 4 CONTRAINDICATIONS 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) ] . Patients with a history of hypersensitivity reaction to succimer. ( 4 )

Side Effects

  • 6 ADVERSE REACTIONS 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.

Interactions

  • 7 DRUG INTERACTIONS CHEMET may interfere with serum and urinary laboratory test. ( 7.1 ) 7.1 Laboratory Test Interference CHEMET may interfere with serum and urinary laboratory tests. In vitro studies have shown CHEMET to cause false positive results for ketones in urine using nitroprusside reagents and falsely decreased measurements of serum uric acid and creatinine phosphokinase (CPK). 7.2 Use with Other Chelation Therapies Concomitant administration of CHEMET with other chelation therapy, such as CaNa 2 EDTA is not recommended.