Mercury when ingested has no effect in the body. The tiny droplets of mercury react with hydrochloric acid in the stomach to form chloride. Instead, when mercury comes into contact with the skin it is absorbed percutaneously, giving rise to the clinical picture known as hydrargyrism. From a biochemical point of view, mercury appears to have an affinity for sulfhydryl binding and is therefore capable of altering cellular metabolism. When mercury salts are ingested, the first symptoms are burning at the oral cavity, followed by constrictive-type pain retrosternally, with vomiting and diarrhea. If, on the other hand, mercury vapors are inhaled, a dry, hacking cough with dyspnea, pyrexia, and muscle aches appears after a few hours.
Diagnosis and treatment
The clinical picture, combined with the medical history, is almost always sufficient to make a diagnosis. Acute metal salt poisoning requires resuscitative treatment with hemodialysis. With metallic mercury the acute symptoms respond to symptomatic type measures so if there are signs of chronic poisoning dimercaprol therapy can be undertaken as with arsenic and with the same precautions.
Source: Vadecum of poisoning therapy by Roy Goulding