↓ Figure 1. Course of severe metabolic acidosis during the first 48 h.
| Journal of Medical Cases, ISSN 1923-4155 print, 1923-4163 online, Open Access |
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Case Report
Volume 17, Number 10, October 2026, pages 578-584
Severe Metformin Intoxication Resulting in Extreme Lactic Acidosis
Figures
Tables
| Risk factor | Comment |
|---|---|
| eGFR: estimated glomerular filtration rate; MALA: metformin-associated lactic acidosis. | |
| Renal impairment | Metformin is contraindicated when eGFR < 30 mL/min/1.73 m2. Renal function should be monitored regularly at eGFR 30–44 mL/min/1.73 m2; ≥ 45 mL/min/1.73 m2 is generally considered safe. |
| Hypoxia or tissue hypoperfusion | Heart failure, severe infection or sepsis, shock, and respiratory failure. |
| Hepatic disease | Liver dysfunction reduces lactate clearance. |
| Alcohol abuse | Alcohol increases lactate production and impairs gluconeogenesis. |
| Acute kidney injury | Often occurs with dehydration, vomiting, diarrhea, or sepsis. |
| Poisoning | Typically involves intentional overdose or suicide attempt, often in patients with renal impairment. |
| Time | Clinical event | pH | Serum lactate (mmol/L) | Serum creatinine (µmol/L) | Treatment |
|---|---|---|---|---|---|
| The clinical course was reconstructed chronologically from the available medical records. CPR: cardiopulmonary resuscitation; CVVH: continuous veno-venous hemofiltration; ED: emergency department; h: hours; ICU: intensive care unit; pH: arterial blood pH; N/A: not available; ↓: decrease. | |||||
| 0 h | Ingestion of 34 g metformin | N/A | N/A | N/A | N/A |
| ED admission | Initial assessment | 7.37 | 10.8 | 96.3 | Fluids |
| +2 h | Progressive acidosis | 7.26 | 18.7 | 121 | Sodium bicarbonate |
| +12 h | Clinical deterioration | 6.86 | 41.7 | 148.7 | CPR |
| +14 h ICU admission | Recurrent cardiac arrest | 6.89 | 39 | 171.2 | Mechanical ventilation |
| 14–24 h ICU | Intermittent hemodialysis | 7.12 | ↓ | 171.2 | Intermittent hemodialysis |
| Department of Anesthesiology days 2–3 | CVVH | 7.27 | ↓ | 119.2 | CVVH |
| ICU days 7–29 | Acute renal failure with anuria | 7.39 | < 3 | Highest level 738 | Intermittent hemodialysis |
| ICU day 29 | Recovery | 7.37 | 0.66 | 260 | Discharge from ICU after 29 days |