78 Review Pyridoxine in clinical toxicology: a review Philippe Lheureux, Andrea Penaloza and Mireille Gris Pyridoxine (vitamin B6) is a co-factor in many enzymatic controversial. This paper reviews the various indications pathways involved in amino acid metabolism: the main of pyridoxine in clinical toxicology and the supporting biologically active form is pyridoxal 5-phosphate. literature. The potential adverse effects of excessive Pyridoxine has been used as an antidote in acute pyridoxine dosage will also be summarized. intoxications, including isoniazid overdose, Gyromitra European Journal of Emergency Medicine 12:78–85 mushroom or false morrel (monomethylhydrazine) c 2005 Lippincott Williams & Wilkins. poisoning and hydrazine exposure. It is also recommended as a co-factor to improve the conversion of glyoxylic acid European Journal of Emergency Medicine 2005, 12:78–85 into glycine in ethylene glycol poisoning. Other indications Keywords: Antidotes, crimidin, drug-induced neuropathy, ethylene glycol, are recommended by some sources (for example crimidine hydrazine, isoniazid, metadoxine, pyridoxine poisoning, zipeprol and theophylline-induced seizures, adjunct to d-penicillamine chelation), without significant Department of Emergency Medicine, Erasme University Hospital, Brussels, Belgium. supporting data. The value of pyridoxine or its congener Correspondence to Philippe Lheureux, Department of Emergency Medicine, metadoxine as an agent for hastening ethanol metabolism Erasme University Hospital, 808 route de Lennik, 1070 Brussels, Belgium. or improving vigilance in acute alcohol intoxication is E-mail:
[email protected] Introduction ing. More controversial issues include alcohol intoxication Pyridoxine or vitamin B6 is a highly water-soluble and zipeprol or theophylline-induced seizures. vitamin. Its main biologically active form is a phosphate ester of its aldehyde form, pyridoxal 5-phosphate (P5P).