Treatment of Mercury Poisoning
The immediate priority in treating mercury poisoning is removing the patient from the source of exposure, followed by chelation therapy with agents such as British anti-Lewisite (BAL), edetate calcium disodium, penicillamine, Sodium 2,3-dimercaptopropane-1-sulfonate (DMPS), or 2,3-dimercaptosuccinic acid (DMSA) for symptomatic patients with confirmed mercury intoxication. 1, 2
Initial Management
Source Removal
- Immediately remove the patient from the mercury exposure source - this is the absolute first priority before any other intervention 1, 3
- For dental amalgam removal specifically, use a rubber dam with high-speed aspiration and abundant irrigation to reduce mercury exposure during the procedure 4
- Ensure proper environmental decontamination to prevent ongoing exposure 3
Diagnostic Confirmation
- Measure urine mercury levels - this is the preferred biological medium for determining exposure to inorganic and elemental mercury 3
- Blood mercury levels can be measured but are unreliable in predicting the severity of mercury toxicity and are only valuable if exposure is ongoing 1, 3
- Hair analysis is not useful for inorganic mercury exposure (only for methylmercury) 3
- Consider a provocation test using chelating agents to evaluate mercury exposure level for diagnosis, though indications are not fully established 2
Chelation Therapy
Available Chelating Agents
The following agents can be used for binding mercury in symptomatic patients 1, 2:
- British anti-Lewisite (BAL/dimercaprol)
- Edetate calcium disodium (EDTA)
- Penicillamine
- Sodium 2,3-dimercaptopropane-1-sulfonate (DMPS)
- 2,3-dimercaptosuccinic acid (DMSA/succimer)
Important Caveats
- Chelation therapy is indicated for symptomatic patients with confirmed mercury poisoning 2, 5
- Indications for chelating agents with mercury exposure have not yet been fully established 2
- Not all unwanted exposures will result in adverse health consequences requiring treatment 3
- Further evaluations are necessary for the effects and side effects of each therapy 2
Additional Treatment Modalities
For severe mercury poisoning, consider 2:
- Combination therapy with multiple chelating agents
- Plasma exchange
- Hemodialysis
- Plasmapheresis
Clinical Presentation to Monitor
Mercury poisoning can present with multiple organ system involvement 1, 6:
- Initial phase: Flu-like illness in the first days 1
- Pulmonary: Respiratory symptoms and pulmonary dysfunction 1
- Neurological: Encephalopathy, polyneuropathy, tremors, erethism (chronic exposure) 1, 6
- Renal: Nephrotic syndrome, kidney damage (particularly with inorganic mercury salts) 1, 6
- Dermatological: Erythematous rash, stomatitis (chronic exposure) 1, 6
- Hepatic and hematological: Liver and blood abnormalities 1
Mechanism of Toxicity
Understanding the pathophysiology helps guide treatment 6: