Lactic Acidosis: What You Need to Know

When dealing with lactic acidosis, a buildup of lactate in the blood that drops pH and threatens organ function. Also known as high lactate syndrome, it signals that cells are generating energy without enough oxygen.

One of the most common drug‑related triggers is Metformin, an oral diabetes medication that can impair lactate clearance, especially when kidney function is reduced. Sepsis, a systemic infection that drives widespread tissue hypoxia and pushes lactate production sky‑high is another powerful driver. When the kidneys can’t filter waste, kidney failure, the organ that normally removes excess lactate, becomes a central piece in the puzzle. Heavy alcohol use also matters; ethanol metabolism creates excess NADH, forcing pyruvate to turn into lactate, a process that can spiral into alcohol intoxication, another frequent cause of elevated blood lactate.

Key Triggers and How They Interact

Lactic acidosis encompasses a variety of underlying conditions, but they share a common pathway: insufficient oxygen for normal aerobic metabolism. Whether the shortage comes from blocked blood flow in shock, a toxic drug effect, or a malfunctioning liver, the result is the same—cells switch to anaerobic glycolysis and dump lactate into the bloodstream. This means clinicians must look for the root cause, not just the high lactate numbers. For example, a patient on Metformin who develops acute kidney injury will need a different approach than a trauma victim in hemorrhagic shock, even though both present with similar lab values.

The clinical picture often includes rapid breathing (to blow off CO₂), nausea, abdominal pain, and a vague sense of “not feeling right.” Blood tests will show a lactate level above 2 mmol/L and a low arterial pH, usually below 7.35. An elevated anion gap helps confirm the diagnosis and narrows down possible culprits. Prompt recognition is crucial because each cause demands a tailored intervention—antibiotics for sepsis, dialysis for kidney failure, or drug discontinuation for Metformin‑related cases.

Treatment strategies follow a three‑step logic: stop the source, support circulation, and clear the lactate. Stopping the offending drug or treating the infection removes the ongoing production. Intravenous fluids and vasopressors improve tissue perfusion, allowing oxygen to reach cells again. In severe cases, sodium bicarbonate or renal replacement therapy may be used to correct the pH while the body clears the excess lactate.

Below you’ll find a curated list of articles that dive deeper into each of these angles—drug‑induced lactic acidosis, sepsis‑related metabolic changes, kidney‑related clearance issues, and practical tips for managing patients in the emergency setting. Use them to sharpen your understanding and guide real‑world decisions.