[Venomous and poisonous animals. II. Viper bites].

Vipers are the main cause of the snake envenomations on all continents except Australia where they are none. Viper envenomation may lead to a minimal inflammatory syndrome with clinical (pain, edema) and biological (hyperleukocytosis, proteinuria) manifestations that may be accompanied by hypotension or shock. Emergency situations are due to hemorrhagic syndrome. In frequent cases in which envenomation is limited to a dramatic decrease in coagulation factors without clinical manifestations, severe local or systemic hemorrhage may occur especially if treatment is delayed. Necrotic complications around the bite or in distant vital organs are not uncommon and require careful medical and surgical surveillance. Intravenous antivenom therapy is the only effective treatment. It should be given as soon as possible but can be effective even when administered several days after the bite.