A person who swallows certain coins may develop zinc intoxication, which can result in copper deficiency. Zinc induces production of metallothionein in enterocytes and this protein tightly binds copper so that it is not available to the body.


People at risk - those with pica and access to coins:

(1) psychiatric patients

(2) small children


The person has to swallow suitable coins in sufficient numbers for a long period of time. Formation of a metal bezoar allows for a long-term exposure to gastric acid. A patient with achlorhydria or hypochlorhydria will leach less metal from the coins and so is at reduced risk.


Coins involved:

(1) pennies in the US (almost 98% zinc)

(2) coins from other countries containing zinc



(1) sideroblastic anemia (associated with copper deficiency)

(2) peripheral neuropathy (associated with zinc intoxication)

(3) high serum and urine zinc levels

(4) low serum copper levels


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