What is the treatment for suspected arsenic poisoning?

Treatment for Suspected Arsenic Poisoning

For suspected arsenic poisoning, immediate medical attention is essential, with treatment involving removal from exposure, supportive care, and chelation therapy with dimercaprol (BAL) for severe cases at a dose of 3 mg/kg every four hours for two days, followed by reduced frequency for ten days. 1

Initial Management

• Immediately activate emergency medical services (EMS) if the patient shows any life-threatening symptoms such as sleepiness, seizures, difficulty breathing, or vomiting 2
• Contact the Poison Help hotline (800-222-1222 in the US) for guidance on treatment approach 2
• Remove the patient from the source of exposure to prevent further contamination 3
• Do not administer anything by mouth (including water or milk) unless specifically advised by poison control or emergency medical personnel 2
• Do not administer activated charcoal or syrup of ipecac unless specifically advised by poison control 2

Diagnostic Considerations

• Distinguish between inorganic arsenic (more toxic) and organic arsenic exposure (less toxic, often from seafood) 4
• If arsenic is in powder form, brush it off the skin with a gloved hand or cloth and remove all contaminated clothing 2
• For skin or eye exposure to arsenic, immediately irrigate the affected area with copious amounts of water 2

Medical Treatment

• For severe cases with significant toxicity, extracorporeal treatment should be considered, with intermittent hemodialysis being the preferred modality 3
• If hemodialysis is not available, continuous kidney replacement therapy (CKRT) is recommended 3
• Peritoneal dialysis may be used in resource-limited settings but is significantly less effective 3

Chelation Therapy

• For mild arsenic poisoning: dimercaprol (BAL) 2.5 mg/kg of body weight four times daily for two days, two times on the third day, and once daily thereafter for ten days 1
• For severe arsenic poisoning: dimercaprol 3 mg/kg every four hours for two days, four times on the third day, then twice daily thereafter for ten days 1
• Dimercaprol is administered by deep intramuscular injection only 1
• Oral chelating agents such as dimercaptosuccinic acid (DMSA) and dimercaptopanesulfonic acid (DMPS) may be used following initial treatment with dimercaprol 5

Special Considerations

• Maintain good folate status to support arsenic elimination from the body 3
• Avoid dimercaprol in patients with known G6PD deficiency due to risk of hemolysis 5
• Dimercaprol should not be used in iron, cadmium, or selenium poisoning as the resulting complexes are more toxic than the metal alone 1
• Arsenic trioxide is highly embryotoxic and requires special consideration during pregnancy 3
• Patients with chronic exposure require long-term monitoring for development of arsenic-related cancers (skin, lung, bladder) 3, 5

Prognosis and Follow-up

• Successful treatment depends on beginning chelation therapy at the earliest possible moment and using adequate amounts at frequent intervals 1
• Supportive care measures should always be used in conjunction with chelation therapy 1
• Long-term follow-up is necessary to monitor for potential complications including peripheral neuropathy, skin changes, and increased cancer risk 5