[Lactic acidosis induced by phenformin: a still forgotten iatrogenic complication]

Phenformin, a drug used in the treatment of diabetes mellitus frequently associated with potentially fatal cases of lactic acidosis, has been removed from market in the USA and several European countries. However, cases of lactic acidosis are still reported in countries where phenformin is available, either because well-known contraindications for its use are not observed, or because the prodromic syndrome of the lactic acidosis is not diagnosed. This study describes two cases of lactic acidosis, the treatment used and the final outcome. The authors point out that plainly evident contraindications were ignored in both cases, while the prodromic syndrome remained unrecognized even by specialists. The management of lactic acidosis continues to be a challenge. There is no optimal treatment and early recognition is essential. The authors call for greater attention in the use of phenformin and its eventual removal from market, especially in the light of alternative therapies which prove to be equally valid and easier to administer.