Metformin-associated lactic acidosis (MALA) is a rare but potentially fatal complication that can occur in a patient on metformin, who had a sudden reduction in the renal function resulting in a raised serum metformin level. We describe a case of MALA who survived with prompt haemodialysis. An elderly female with diabetes on metformin presented with gastrointestinal losses, lethargy and confusion. She was in circulatory shock and despite an aggressive fluid regime, she remained acidotic with an increasing lactate level of > 15 mmol/L. After endotracheal intubation, she was referred to tertiary centre for haemodialysis. Her serum lactate level rapidly fell to a satisfactory range and a progressive recovery followed. We are highlighting this case for its rarity and to serve as a guidance on the early recognition of MALA for fellow clinicians. Despite the high mortality rate, MALA is reversible, and we urge clinicians to expedite haemodialysis as definitive treatment.