Metabolic acidosis: differentiating the causes in the poisoned patient.

Metabolic acidosis may arise from several drugs and toxins through a variety of mechanisms. Differentiating the causes of metabolic acidosis in the poisoned patient is an indispensable skill in clinical practice. Comprehension of toxin-induced metabolic acidosis, combined with a thorough history, physical examination, appropriate use of laboratory tests, and a stepwise approach, should aid the clinician in determining the cause of metabolic acidosis in the poisoned patient. When confronted with such a patient, it is imperative that one administer appropriate antidotal therapy, when necessary, and provide the patient with exceptional supportive care.