View source for Zinc toxicity

==Background==
*Transition metal
*Essential nutrient
*Exposure from diet, medicinal uses, nutritional supplements, and occupational exposures
**Multiple case reports of zinc toxicity related to ingestion of United States pennies which contain 97.5% zinc

===Toxicokinetics===
*Absorbed primarily in the jejunum
*Excreted via the GI tract with minimal amounts excreted in the urine
*Accumulates in erythrocytes
**Whole blood concentrations are 6-7x higher than in the serum
*Inverse relationship with copper
**Excess zinc absorption will cause a counterregulatory response resulting in copper elimination

==Clinical Features==
===Acute===
*GI distress
**[[Nausea]]
**[[Vomiting]]
**[[Abdominal pain]]
**[[GI bleeding]]
**Partial and full thickness burns causing strictures with zinc chloride solutions with >20% zinc
*Inhalation
**Lacrimation
**Rhinitis
**[[Dyspnea]]
**Acute lung injury
**[[Acute Respiratory Distress Syndrome]]
**[[Metal fume fever]]

===Chronic===
*Zinc induced copper deficiency
**Reversible sideroblastic [[anemia]]
**Reversible [[myelodysplastic syndrome]]
*Progressive myeloneuropathy
**Spastic gait
**Sensory [[ataxia]]

==Differential Diagnosis==
{{Heavy metals list}}

==Evaluation==
*BMP
*CBC
*Copper level
*Ceruloplasmin level
*Abdominal films to assess for foreign bodies
*[[brain MRI|MRI]]
**Will show increase T<sub>2</sub> signal in the dorsal columns of the cervical cord

==Management==
*Oral toxicity
**Supportive Care
***[[IVF|Hydration]]
***[[H2 blocker|H<sub>2</sub> receptor antagonists]] or [[PPI]]
***[[Antiemetics]]
**Consider [[whole bowel irrigation]]
*Inhalation
**Supportive care
***[[Oxygen therapy]]
***[[Bronchodilators]]
**[[Metal fume fever]]
***Usually self limiting
***[[CXR]] usually normal
*Chelation
**Limited data on use, and data present is based off of case reports and treatment for lead toxicity <ref>Majlesi, N. Zinc. In: Goldfrank's Toxicologic Emergencies. 9th Ed. New York: McGraw-Hill; 2011: 1342</ref>
**Consider in patients with hemodynamic compromise
**CaNa<sub>2</sub>[[EDTA]], [[British antilewisite]], DTPA were all successfully used in case reports
**1000mg/m<sup>2</sup>/d IV CaNa<sub>2</sub>EDTA every 6 hours
***Based on a successful case report, but should be given in conjunction with toxicology or poison control center
*Dermal Exposures
**Do not use water in metallic zinc exposures
***Concern metal will ignite
**Remove zinc with forceps and apply mineral oil to affected skin
*Copper replacement
**Oral copper alone shown to improve hematopoietic effects and prevent further neurological deterioration <ref> Rowin J, Lewis SL. Copper deficiency myeloneuropathy and pancytopenia secondary to overuse of zinc supplementation. J Neurol Neurosurg Psychiatry. 2005;76:750-751. </ref>

==Disposition==
*Consult Toxicology or [[poison control]]

==References==
<references/>

[[Category:Toxicology]]