Parenteral chelation therapy
Urgent parenteral chelation therapy is required for patients who present with lead encephalopathy (altered conscious state or seizures in the context of lead exposure). Appropriate regimens for adults and children are:
1 dimercaptopropane-1-sulfonate (DMPS) 5 mg/kg intravenously, every 6 hours for 5 days1 lead poisoning
OR as combination therapy
2 dimercaprol 3 mg/kg intramuscularly, every 4 hours for 2 days, then reduce to 3 mg/kg every 12 hours for a further 5 to 7 days2 lead poisoning
PLUS
sodium calcium edetate (calcium EDTA) 50 to 75 mg/kg in crystalloid solution 500 mL3 intravenously over 24 hours, daily for up to 5 days4. lead poisoning
Sodium calcium edetate can be used as a single agent if the other parenteral agents are not available. It can cause kidney injury and prolonged treatment can lead to significant micronutrient deficiencies.
If the patient does not have lead encephalopathy (ie parenteral chelation therapy was used because oral therapy was indicated but not available), treatment should be switched to oral chelation therapy with succimer as soon as it becomes available (see Oral chelation therapy). Succimer should be used for at least 14 days after parenteral chelation therapy. For advice on the further management of lead poisoning, see Monitoring and follow up after chelation therapy.