The Serum Lactate Level and Other Factors in Metformin Poisoning: A Case Series

Identifying the effective factors in the progression toward lactic acidosis and death is essential in improving the treatment of Metformin-poisoned patients. This study investigates the blood lactate level in Metformin-poisoned patients and the factors affecting it.

This was a case series study in two referral clinical toxicology centers in Iran for one year. 16 patients were included in the study. The questionnaire was filled out based on the demographic characteristics of the person, vital signs, poisoning symptoms, blood biochemistry, blood gases, blood sugar, and treatments. The lactate level was measured 6-12-24 hours later.

Three cases (18.8%) were male and 13 (81.3%) were female. The average age was 30.13 ± 16.22 years. One case of hypoglycemia, three cases of metabolic acidosis, and three cases of creatinine level above 1.2 were observed. The initial pH and bicarbonate were predictors of the lactate level. No cases of death or lactic acidosis were observed.

Blood pH and bicarbonate can be used as predictors of serum lactate increase. Also, this study showed that the probability of death and lactic acidosis with metformin is very low.