[Metformin-associated lactic acidosis: an insufficiently recognised problem]

Metformin-associated lactic acidosis (MALA) is a rare but potentially fatal condition that can easily be avoided. As metformin is known to facilitate the production of lactate, predisposing factors can accelerate this process. In situations of infection or dehydration, metformin can accumulate due to kidney failure, hereby increasing the risk of MALA. Despite controversy in the literature about the presence of a relationship between metformin and lactic acidosis, the severity of the condition is cause for concern and allows for preventive measurements. Awareness of this condition among patients and clinicians is insufficient, resulting in many patients continuing metformin in situations where there is an increased risk of developing MALA. Metformin can easily be discontinued temporarily without causing any harm. We emphasize the importance of temporarily discontinuing metformin in situations where the risk of lactic acidosis is increased, such as severe infection, dehydration and acute kidney insufficiency. This requires increased awareness and adequate counselling by clinicians as well as pharmacists.