Efficacy of orally administered deferoxamine, activated charcoal, and sodium bicarbonate in acute iron intoxication in rats: implications for the treatment of pediatric iron poisoning

Abstract

Background: Iron supplements are the most frequent cause of pediatric fatalities from unintentional ingestion. The ability to prevent iron absorption from the digestive tract is limited. Although activated charcoal (AC) alone does not absorb iron, the oral administration of deferoxamine (DFO) and AC has been shown to reduce iron absorption in human volunteers. In the presence of sodium bicarbonate (NaHCO 3), ferrous iron is oxidized to ferric iron. Therefore, the coadministration of DFO, AC, and NaHCO 3 may enhance enteral iron chelation. Objective: The purpose of the study was to determine whether the oral administration of DFO and AC, with or without NaHCO 3, can reduce iron absorption from the digestive tract. Methods: In a rat model of acute iron overloading, ferrous sulfate (FeSO 4) 100 mg/kg body weight was administered by gavage, followed by DFO 150 mg/kg, AC 500 mg/kg, and NaHCO 3 1 mEq/kg. Results: The administration of FeSO 4 100 mg/kg increased serum iron concentrations to > 350 μg/100 mL. Oral dosing with DFO and AC (separately and simultaneously, immediately or after 10 to 20 minutes) did not prevent iron absorption from the digestive tract. Subsequently, however, DFO significantly decreased the elevated serum iron concentrations ( P < 0.05), probably by chelating the already absorbed iron. Coadministration of NaHCO 3 further decreased ( P < 0.01) the serum iron concentration. Conclusions: Although orally administered DFO and AC do not prevent iron absorption from the digestive tract, DFO does increase the rate of iron excretion from the body, and NaHCO 3 enhances this effect.