An evaluation of the interference of hydroxycobalamin with chemistry and co-oximetry tests on nine commonly used instruments.

The administration of hydroxocobalamin (OHCob), alone or with sodium thiosulfate, is a standard therapy for cyanide poisoning. OHCob is a red chromophore, and its interference with co-oximetric and colorimetric laboratory measurements has been evaluated in a few conflicting reports. The interference of OHCob was investigated in samples spiked with 10 different concentrations of OHCob (0-1500 mg/L).