Levels drawn more than 6 hours after ingestion may underestimate toxicity caused by ferritin binding and redistribution of iron. Samples drawn too early or too late postingestion may be unreliable. In adults, hyperglycemia, leukocytosis, abdominal pain, and vomiting may be absent. Following glucose levels is important because hepatic dysfunction may cause hypoglycemia. A CBC is also helpful because anemia from blood loss may develop.
Coagulation studies are essential.
Following the prothrombin time may be helpful. Hepatic dysfunction is common in severe iron poisoning because the liver is the first organ outside of the GI tract to encounter iron. Electrolyte measurements and renal function tests assist in calculation of the anion gap and detection of electrolyte abnormalities and the presence of prerenal azotemia. Lipase and amylase levels may document occasional pancreatic injury. Obtain a pregnancy test in women of childbearing age.